diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_autofill_related_realms_no_dupes.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_autofill_related_realms_no_dupes.html
index f885794476fa..19b6bee97a27 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_autofill_related_realms_no_dupes.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_autofill_related_realms_no_dupes.html
@@ -75,10 +75,10 @@ add_setup(async () => {
 add_task(async function test_no_duplicates_autocomplete_autofill() {
   await promiseFormsProcessedInSameProcess();
   await SimpleTest.promiseFocus(window);
-  let shownPromise = promiseACShown();
-  checkLoginForm(uname, "exactUser1", pword, "exactPass1")
-  restoreForm();
-  let results = await shownPromise;
+  let results = await popupBy(() => {
+    checkLoginForm(uname, "exactUser1", pword, "exactPass1")
+    restoreForm();
+  });
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entires are selected upon opening");
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form.html
index 1d7d3425b5c1..e24736aa93ac 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form.html
@@ -170,7 +170,7 @@ add_task(async function test_form1_menuitems() {
   await SimpleTest.promiseFocus(window);
   // Trigger autocomplete popup
   restoreForm();
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupByArrowDown();
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
@@ -200,7 +200,7 @@ add_task(async function test_form1_first_entry() {
   await SimpleTest.promiseFocus(window);
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
@@ -216,7 +216,7 @@ add_task(async function test_form1_first_entry() {
 add_task(async function test_form1_second_entry() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // first
   synthesizeKey("KEY_ArrowDown"); // second
@@ -229,7 +229,7 @@ add_task(async function test_form1_second_entry() {
 add_task(async function test_form1_third_entry() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // first
   synthesizeKey("KEY_ArrowDown"); // second
@@ -243,7 +243,7 @@ add_task(async function test_form1_third_entry() {
 add_task(async function test_form1_fourth_entry() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // first
   synthesizeKey("KEY_ArrowDown"); // second
@@ -259,7 +259,7 @@ add_task(async function test_form1_wraparound_first_entry() {
   // Trigger autocomplete popup
   restoreForm();
   await spinEventLoop(); // let focus happen
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // first
   synthesizeKey("KEY_ArrowDown"); // second
@@ -277,7 +277,7 @@ add_task(async function test_form1_wraparound_first_entry() {
 add_task(async function test_form1_wraparound_up_last_entry() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowUp"); // footer
   synthesizeKey("KEY_ArrowUp"); // last (fourth)
@@ -290,7 +290,7 @@ add_task(async function test_form1_wraparound_up_last_entry() {
 add_task(async function test_form1_wraparound_down_up_up() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // select first entry
   synthesizeKey("KEY_ArrowUp"); // selects nothing!
@@ -304,7 +304,7 @@ add_task(async function test_form1_wraparound_down_up_up() {
 
 add_task(async function test_form1_wraparound_up_last() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown");
   synthesizeKey("KEY_ArrowUp"); // deselects
@@ -324,7 +324,7 @@ add_task(async function test_form1_wraparound_up_last() {
 
 add_task(async function test_form1_fill_username_without_autofill_right() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Set first entry w/o triggering autocomplete
   synthesizeKey("KEY_ArrowDown"); // first
@@ -335,7 +335,7 @@ add_task(async function test_form1_fill_username_without_autofill_right() {
 
 add_task(async function test_form1_fill_username_without_autofill_left() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Set first entry w/o triggering autocomplete
   synthesizeKey("KEY_ArrowDown"); // first
@@ -346,7 +346,7 @@ add_task(async function test_form1_fill_username_without_autofill_left() {
 
 add_task(async function test_form1_pageup_first() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check first entry (page up)
   synthesizeKey("KEY_ArrowDown"); // first
@@ -360,7 +360,7 @@ add_task(async function test_form1_pageup_first() {
 
 add_task(async function test_form1_pagedown_last() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   /* test 13 */
   // Check last entry (page down)
@@ -387,7 +387,7 @@ add_task(async function test_form1_untrusted_event() {
 
 add_task(async function test_form1_delete() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // XXX tried sending character "t" before/during dropdown to test
   // filtering, but had no luck. Seemed like the character was getting lost.
@@ -418,7 +418,7 @@ add_task(async function test_form1_delete() {
 
 add_task(async function test_form1_first_after_deletion() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check the new first entry (of 3)
   synthesizeKey("KEY_ArrowDown");
@@ -430,7 +430,7 @@ add_task(async function test_form1_first_after_deletion() {
 
 add_task(async function test_form1_delete_second() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Delete the second entry (of 3), "testuser3"
   synthesizeKey("KEY_ArrowDown");
@@ -447,7 +447,7 @@ add_task(async function test_form1_delete_second() {
 
 add_task(async function test_form1_first_after_deletion2() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check the new first entry (of 2)
   synthesizeKey("KEY_ArrowDown");
@@ -459,7 +459,7 @@ add_task(async function test_form1_first_after_deletion2() {
 
 add_task(async function test_form1_delete_last() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   /* test 54 */
   // Delete the last entry (of 2), "zzzuser4"
@@ -478,7 +478,7 @@ add_task(async function test_form1_delete_last() {
 
 add_task(async function test_form1_first_after_3_deletions() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check the only remaining entry
   synthesizeKey("KEY_ArrowDown");
@@ -490,7 +490,7 @@ add_task(async function test_form1_first_after_3_deletions() {
 
 add_task(async function test_form1_check_only_entry_remaining() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   /* test 56 */
   // Delete the only remaining entry, "testuser2"
@@ -526,7 +526,7 @@ add_task(async function test_form2() {
   checkLoginForm(uname, "singleuser5", pword, "singlepass5");
 
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check first entry
   synthesizeKey("KEY_ArrowDown");
@@ -549,7 +549,7 @@ add_task(async function test_form3() {
   pword = getFormElementByName(3, "pword");
   checkLoginForm(uname, "singleuser5", pword, "singlepass5");
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check first entry
   synthesizeKey("KEY_ArrowDown");
@@ -572,7 +572,7 @@ add_task(async function test_form4() {
   pword = getFormElementByName(4, "pword");
   checkLoginForm(uname, "singleuser5", pword, "singlepass5");
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check first entry
   synthesizeKey("KEY_ArrowDown");
@@ -595,7 +595,7 @@ add_task(async function test_form5() {
   pword = getFormElementByName(5, "pword");
   checkLoginForm(uname, "singleuser5", pword, "singlepass5");
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check first entry
   synthesizeKey("KEY_ArrowDown");
@@ -675,7 +675,7 @@ add_task(async function test_form7() {
 add_task(async function test_form7_2() {
   restoreForm();
 
-  const autocompleteItems = await openAutocompletePopup();;
+  const autocompleteItems = await popupByArrowDown();
   checkAutoCompleteResults(autocompleteItems,
                            ["form7user1"],
                            window.location.host,
@@ -755,20 +755,16 @@ add_task(async function test_form9_filtering() {
     </form>`, {fieldSelector: `input[name="uname"]`, fieldValue: ""});
 
   // Turn our attention to form9 to test the dropdown - bug 497541
-  let shownPromise = promiseACShown();
   uname = getFormElementByName(9, "uname");
   pword = getFormElementByName(9, "pword");
-  uname.focus();
-  let results = await shownPromise;
+  let results = await popupBy(() => uname.focus());
   checkAutoCompleteResults(results,
                            ["form9userAAB", "form9userAB"],
                            window.location.host,
                            "Check dropdown is showing all logins while field is blank");
   synthesizeKey("KEY_Escape"); // Need to close the popup so we can get another popupshown after sending the string below.
 
-  shownPromise = promiseACShown();
-  sendString("form9userAB");
-  results = await shownPromise;
+  results = await popupBy(() => sendString("form9userAB"));
   checkAutoCompleteResults(results,
                            ["form9userAB"],
                            window.location.host,
@@ -777,9 +773,7 @@ add_task(async function test_form9_filtering() {
   checkLoginForm(uname, "form9userAB", pword, "");
   uname.focus();
   synthesizeKey("KEY_ArrowLeft");
-  shownPromise = promiseACShown();
-  synthesizeKey("A", {shiftKey: true});
-  results = await shownPromise;
+  results = await popupBy(() => synthesizeKey("A", {shiftKey: true}));
 
   checkLoginForm(uname, "form9userAAB", pword, "");
   checkAutoCompleteResults(results, ["form9userAAB"],
@@ -833,7 +827,7 @@ add_task(async function test_form11_formless() {
   pword = getFormElementByName(11, "pword");
   restoreForm();
   checkLoginForm(uname, "", pword, "");
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Trigger autocomplete
   synthesizeKey("KEY_ArrowDown");
@@ -861,10 +855,10 @@ add_task(async function test_form11_open_on_trusted_focus() {
       resolve();
     });
   });
-  const shownPromise = promiseACShown();
-  synthesizeMouseAtCenter(uname, {});
-  await firePrivEventPromise;
-  await shownPromise;
+  await popupBy(async () => {
+    synthesizeMouseAtCenter(uname, {});
+    await firePrivEventPromise;
+  });
   synthesizeKey("KEY_ArrowDown");
   const processedPromise = promiseFormsProcessedInSameProcess();
   synthesizeKey("KEY_Enter");
@@ -905,7 +899,7 @@ add_task(async function test_form12_recipes() {
   await promiseFormsProcessedInSameProcess();
   restoreForm();
   checkLoginForm(uname, "", pword, "");
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown");
   checkLoginForm(uname, "", pword, ""); // value shouldn't update
@@ -939,9 +933,7 @@ add_task(async function test_form13_stays_open_upon_empty_search() {
   checkLoginForm(uname, "prefilled", pword, "prefilled");
 
   uname.scrollIntoView();
-  let shownPromise = promiseACShown();
-  synthesizeMouseAtCenter(uname, {});
-  await shownPromise;
+  await popupBy(() => synthesizeMouseAtCenter(uname, {}));
   uname.select();
   synthesizeKey("KEY_Delete");
 
@@ -955,9 +947,7 @@ add_task(async function test_form13_stays_open_upon_empty_search() {
   pword.select();
   popupState = await getPopupState();
   is(popupState.open, false, "Check popup closed since password field isn't empty");
-  shownPromise = promiseACShown();
-  synthesizeKey("KEY_Delete");
-  await shownPromise;
+  await popupBy(() => synthesizeKey("KEY_Delete"));
   checkLoginForm(uname, "", pword, "");
 
   // ensure the popup is closed for the next test
@@ -982,7 +972,7 @@ add_task(async function test_form14_username_only() {
   pword = {value: ""};
   checkLoginForm(uname, "prefilled", pword, "");
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check first entry
   synthesizeKey("KEY_ArrowDown");
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_formActionOrigin.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_formActionOrigin.html
index 541f8391bdda..bbc57824b94c 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_formActionOrigin.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_formActionOrigin.html
@@ -70,7 +70,7 @@ add_task(async function test_form1_menu_shows_logins_for_different_formActionOri
   await SimpleTest.promiseFocus(window);
   // Trigger autocomplete popup
   restoreForm();
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupByArrowDown();
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_insecure.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_insecure.html
index b06c4db587b3..8b6f90d68993 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_insecure.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_insecure.html
@@ -142,7 +142,7 @@ add_task(async function test_form1_warning_entry() {
   await SimpleTest.promiseFocus(window);
   // Trigger autocomplete popup
   restoreForm();
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupByArrowDown();
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
@@ -165,7 +165,7 @@ add_task(async function test_form1_first_entry() {
   await SimpleTest.promiseFocus(window);
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
@@ -181,7 +181,7 @@ add_task(async function test_form1_first_entry() {
 add_task(async function test_form1_second_entry() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   synthesizeKey("KEY_ArrowDown"); // first
@@ -194,7 +194,7 @@ add_task(async function test_form1_second_entry() {
 add_task(async function test_form1_third_entry() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   synthesizeKey("KEY_ArrowDown"); // first
@@ -208,7 +208,7 @@ add_task(async function test_form1_third_entry() {
 add_task(async function test_form1_fourth_entry() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   synthesizeKey("KEY_ArrowDown"); // first
@@ -224,7 +224,7 @@ add_task(async function test_form1_wraparound_first_entry() {
   // Trigger autocomplete popup
   restoreForm();
   await spinEventLoop(); // let focus happen
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   synthesizeKey("KEY_ArrowDown"); // first
@@ -243,7 +243,7 @@ add_task(async function test_form1_wraparound_first_entry() {
 add_task(async function test_form1_wraparound_up_last_entry() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowUp"); // footer
   synthesizeKey("KEY_ArrowUp"); // last (fourth)
@@ -255,7 +255,7 @@ add_task(async function test_form1_wraparound_up_last_entry() {
 add_task(async function test_form1_wraparound_down_up_up() {
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // select first entry
   synthesizeKey("KEY_ArrowUp"); // selects nothing!
@@ -268,7 +268,7 @@ add_task(async function test_form1_wraparound_down_up_up() {
 
 add_task(async function test_form1_wraparound_up_last() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown");
   synthesizeKey("KEY_ArrowUp"); // deselects
@@ -288,7 +288,7 @@ add_task(async function test_form1_wraparound_up_last() {
 
 add_task(async function test_form1_fill_username_without_autofill_right() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Set first entry w/o triggering autocomplete
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
@@ -300,7 +300,7 @@ add_task(async function test_form1_fill_username_without_autofill_right() {
 
 add_task(async function test_form1_fill_username_without_autofill_left() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Set first entry w/o triggering autocomplete
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
@@ -311,7 +311,7 @@ add_task(async function test_form1_fill_username_without_autofill_left() {
 
 add_task(async function test_form1_pageup_first() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // Check first entry (page up)
   synthesizeKey("KEY_ArrowDown"); // first
@@ -325,7 +325,7 @@ add_task(async function test_form1_pageup_first() {
 
 add_task(async function test_form1_pagedown_last() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // test 13
   // Check last entry (page down)
@@ -351,7 +351,7 @@ add_task(async function test_form1_untrusted_event() {
 
 add_task(async function test_form1_delete() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   // XXX tried sending character "t" before/during dropdown to test
   // filtering, but had no luck. Seemed like the character was getting lost.
@@ -383,7 +383,7 @@ add_task(async function test_form1_delete() {
 
 add_task(async function test_form1_first_after_deletion() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Check the new first entry (of 3)
@@ -395,7 +395,7 @@ add_task(async function test_form1_first_after_deletion() {
 
 add_task(async function test_form1_delete_second() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Delete the second entry (of 3), "testuser3"
@@ -414,7 +414,7 @@ add_task(async function test_form1_delete_second() {
 
 add_task(async function test_form1_first_after_deletion2() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Check the new first entry (of 2)
@@ -426,7 +426,7 @@ add_task(async function test_form1_first_after_deletion2() {
 
 add_task(async function test_form1_delete_last() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // test 54
@@ -448,7 +448,7 @@ add_task(async function test_form1_delete_last() {
 
 add_task(async function test_form1_first_after_3_deletions() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Check the only remaining entry
@@ -460,7 +460,7 @@ add_task(async function test_form1_first_after_3_deletions() {
 
 add_task(async function test_form1_check_only_entry_remaining() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // test 56
@@ -496,7 +496,7 @@ add_task(async function test_form2() {
   checkLoginForm(uname, "singleuser5", pword, "singlepass5");
 
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Check first entry
@@ -519,7 +519,7 @@ add_task(async function test_form3() {
   pword = getFormElementByName(3, "pword");
   checkLoginForm(uname, "singleuser5", pword, "singlepass5");
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Check first entry
@@ -542,7 +542,7 @@ add_task(async function test_form4() {
   pword = getFormElementByName(4, "pword");
   checkLoginForm(uname, "singleuser5", pword, "singlepass5");
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Check first entry
@@ -565,7 +565,7 @@ add_task(async function test_form5() {
   pword = getFormElementByName(5, "pword");
   checkLoginForm(uname, "singleuser5", pword, "singlepass5");
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Check first entry
@@ -644,7 +644,7 @@ add_task(async function test_form7() {
 
 add_task(async function test_form7_2() {
   restoreForm();
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   // Check first entry
@@ -719,19 +719,17 @@ add_task(async function test_form9_filtering() {
     </form>`, {fieldSelector: `input[name="uname"]`, fieldValue: ""});
 
   // Turn our attention to form9 to test the dropdown - bug 497541
-  let shownPromise = promiseACShown();
-  uname = getFormElementByName(9, "uname");
-  pword = getFormElementByName(9, "pword");
-  uname.focus();
-  let results = await shownPromise;
+  let results = await popupBy(() => {
+    uname = getFormElementByName(9, "uname");
+    pword = getFormElementByName(9, "pword");
+    uname.focus();
+  });
   checkAutoCompleteResults(results,
                            ["This connection is not secure. Logins entered here could be compromised. Learn More", "form9userAAB", "form9userAB"],
                            "mochi.test",
                            "Check dropdown is showing all logins while field is blank");
   synthesizeKey("KEY_Escape"); // Need to close the popup so we can get another popupshown after sending the string below.
-  shownPromise = promiseACShown();
-  sendString("form9userAB");
-  results = await shownPromise;
+  results = await popupBy(() => sendString("form9userAB"));
   checkAutoCompleteResults(results,
                            ["This connection is not secure. Logins entered here could be compromised. Learn More", "form9userAB"],
                            "mochi.test",
@@ -740,9 +738,7 @@ add_task(async function test_form9_filtering() {
   checkLoginForm(uname, "form9userAB", pword, "");
   uname.focus();
   synthesizeKey("KEY_ArrowLeft");
-  shownPromise = promiseACShown();
-  synthesizeKey("A", {shiftKey: true});
-  results = await shownPromise;
+  results = await popupBy(() => synthesizeKey("A", {shiftKey: true}));
 
   checkLoginForm(uname, "form9userAAB", pword, "");
   checkAutoCompleteResults(results,
@@ -765,7 +761,7 @@ add_task(async function test_form9_autocomplete_cache() {
   await storageChanged;
   uname.focus();
   let promise2 = notifyMenuChanged(2);
-  let shownPromise = promiseACShown();
+  let shownPromise = popupBy();
   sendString("z");
   let results = await promise2;
   await shownPromise;
@@ -817,7 +813,7 @@ add_task(async function test_form11_recipes() {
   await promiseFormsProcessedInSameProcess();
   restoreForm();
   checkLoginForm(uname, "", pword, "");
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // skip insecure warning
   synthesizeKey("KEY_ArrowDown");
@@ -849,9 +845,9 @@ add_task(async function test_form12_formless() {
 
   uname = getFormElementByName(12, "uname");
   pword = getFormElementByName(12, "pword");
-  await openAutocompletePopup(uname);
+  await openPopupOn(uname);
   synthesizeKey("KEY_Escape"); // close the autocomplete popup
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupByArrowDown();
 
   let expectedMenuItems = ["This connection is not secure. Logins entered here could be compromised. Learn More",
                            "testuser10"];
@@ -879,9 +875,7 @@ add_task(async function test_form13_stays_open_upon_empty_search() {
   checkLoginForm(uname, "prefilled", pword, "prefilled");
 
   uname.scrollIntoView();
-  let shownPromise = promiseACShown();
-  synthesizeMouseAtCenter(uname, {});
-  await shownPromise;
+  await popupBy(() => synthesizeMouseAtCenter(uname, {}));
   uname.select();
   synthesizeKey("KEY_Delete");
 
@@ -895,9 +889,7 @@ add_task(async function test_form13_stays_open_upon_empty_search() {
   pword.select();
   popupState = await getPopupState();
   is(popupState.open, false, "Check popup closed since password field isn't empty");
-  shownPromise = promiseACShown();
-  synthesizeKey("KEY_Delete");
-  await shownPromise;
+  await popupBy(() => synthesizeKey("KEY_Delete"));
   checkLoginForm(uname, "", pword, "");
 });
 </script>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_related_realms.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_related_realms.html
index dba17ce06f41..0178ed02bd28 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_related_realms.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_related_realms.html
@@ -81,7 +81,7 @@ add_task(async function test_form1_initial_empty() {
 add_task(async function test_form_related_domain_menuitems() {
   await SimpleTest.promiseFocus(window);
   restoreForm();
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupByArrowDown();
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entires are selected upon opening");
 
@@ -107,7 +107,7 @@ add_task(async function test_form_related_domain_menuitems() {
 
   restoreForm();
 
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // first item
   synthesizeKey("KEY_ArrowDown"); // second item
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_subdomain.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_subdomain.html
index 0a6177d85a73..1cfd67a0a43f 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_subdomain.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_subdomain.html
@@ -94,7 +94,7 @@ add_task(async function test_form1_menu_shows_two_logins_same_usernames_for_diff
   await SimpleTest.promiseFocus(window);
   // Trigger autocomplete popup
   restoreForm();
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupByArrowDown();
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
@@ -116,7 +116,7 @@ add_task(async function test_form1_menu_shows_two_logins_same_usernames_for_diff
 
   restoreForm();
 
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // first item
   synthesizeKey("KEY_ArrowDown"); // second item
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_hasBeenTypePassword.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_hasBeenTypePassword.html
index fabfe038e60a..f67f302e87f1 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_hasBeenTypePassword.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_hasBeenTypePassword.html
@@ -68,7 +68,7 @@ add_task(async function test_form1_password_to_type_text() {
 
   // Trigger autocomplete popup
   restoreForm();
-  const autocompleteItems =  await openAutocompletePopup();
+  const autocompleteItems =  await popupByArrowDown();
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
@@ -90,7 +90,7 @@ add_task(async function test_form1_password_to_type_text() {
   info("Focusing the password field");
   pword.focus();
 
-  await openAutocompletePopup();
+  await popupByArrowDown();
 
   synthesizeKey("KEY_ArrowDown"); // first item
   checkLoginForm(uname, "", pword, ""); // value shouldn't update just by selecting
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight.html
index 49f1c11180a8..68dfe81f02cb 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight.html
@@ -42,7 +42,7 @@ add_task(async function test_field_highlight_on_autocomplete() {
   let username = document.getElementById("uname");
   let password = document.getElementById("pword");
 
-  await openAutocompletePopup(username);
+  await openPopupOn(username);
   synthesizeKey("KEY_ArrowDown");
   await synthesizeKey("KEY_Enter");
 
@@ -72,7 +72,7 @@ add_task(async function test_field_highlight_on_autocomplete() {
   password.value = "";
 
   // Test password field autocomplete.
-  await openAutocompletePopup(password);
+  await openPopupOn(password);
   synthesizeKey("KEY_ArrowDown");
   synthesizeKey("KEY_Enter");
 
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_non_login.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_non_login.html
index 2c3df90184b2..cabab173be28 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_non_login.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_non_login.html
@@ -40,7 +40,7 @@ add_setup(async () => {
 add_task(async function test_field_highlight_on_pw_field_autocomplete_insecureWarning() {
   // Press enter on insecure warning and check.
   password.focus();
-  await openAutocompletePopup();
+  await popupByArrowDown();
   synthesizeKey("KEY_ArrowDown"); // insecure warning
   synthesizeKey("KEY_Enter");
 
@@ -51,7 +51,7 @@ add_task(async function test_field_highlight_on_pw_field_autocomplete_insecureWa
      "Highlight is not applied to the username field if enter key is pressed on the insecure warning item");
 
   // Press tab on insecure warning and check.
-  await openAutocompletePopup(password);
+  await openPopupOn(password);
   synthesizeKey("KEY_ArrowDown"); // insecure warning
   synthesizeKey("KEY_Tab");
 
@@ -71,7 +71,7 @@ function closeCurrentTab() {
 
 add_task(async function test_field_highlight_on_pw_field_autocomplete_footer() {
   // Press enter on the footer and check.
-  await openAutocompletePopup(password);
+  await openPopupOn(password);
   synthesizeKey("KEY_ArrowUp"); // footer
   synthesizeKey("KEY_Enter");
 
@@ -84,7 +84,7 @@ add_task(async function test_field_highlight_on_pw_field_autocomplete_footer() {
   closeCurrentTab();
 
   // Press tab on the footer and check.
-  await openAutocompletePopup(password);
+  await openPopupOn(password);
   synthesizeKey("KEY_ArrowUp"); // footer
   synthesizeKey("KEY_Tab");
 
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_username_only_form.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_username_only_form.html
index 8a9e035ed2ba..b903fec6a876 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_username_only_form.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_username_only_form.html
@@ -40,7 +40,7 @@ add_task(async function test_username_field_in_username_only_form_highlight_on_a
   // Test username autocomplete.
   const username = document.getElementById("uname");
 
-  await openAutocompletePopup(username);
+  await openPopupOn(username);
   synthesizeKey("KEY_ArrowDown");
   await synthesizeKey("KEY_Enter");
 
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_downgrade.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_downgrade.html
index e3d4b0fff0c5..f103fd64ca71 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_downgrade.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_downgrade.html
@@ -94,7 +94,7 @@ add_task(async function test_autocomplete_https_downgrade() {
   await restoreForm();
   let popupState = await getPopupState();
   is(popupState.open, false, "Check popup is initially closed");
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupByArrowDown();
   info("got results: " + autocompleteItems.join(", "));
   popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected");
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_upgrade.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_upgrade.html
index c041e7fd5c4a..31059d7da5bd 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_upgrade.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_upgrade.html
@@ -80,7 +80,7 @@ add_task(async function test_empty_first_entry() {
   await restoreForm();
   let popupState = await getPopupState();
   is(popupState.open, false, "Check popup is initially closed");
-  let autocompleteItems = await openAutocompletePopup();
+  let autocompleteItems = await popupBy();
   popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected");
   checkAutoCompleteResults(autocompleteItems, ["name", "name1", "name2"], hostname, "initial");
@@ -97,7 +97,7 @@ add_task(async function test_empty_first_entry() {
 
 add_task(async function test_empty_second_entry() {
   await restoreForm();
-  await openAutocompletePopup();
+  await popupBy();
   synthesizeKey("KEY_ArrowDown"); // first
   synthesizeKey("KEY_ArrowDown"); // second
   synthesizeKey("KEY_Enter");
@@ -107,19 +107,18 @@ add_task(async function test_empty_second_entry() {
 
 add_task(async function test_search() {
   await restoreForm();
-  let shownPromise = promiseACShown();
+  let results = await popupBy(async () => {
+    // We need to blur for the autocomplete controller to notice the forced value below.
+    await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+      let uname = this.content.document.getElementById("form-basic-username");
+      uname.blur();
+      uname.value = "name";
+      uname.focus();
+    });
 
-  // We need to blur for the autocomplete controller to notice the forced value below.
-  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
-    let uname = this.content.document.getElementById("form-basic-username");
-    uname.blur();
-    uname.value = "name";
-    uname.focus();
+    sendChar("1");
+    synthesizeKey("KEY_ArrowDown"); // open
   });
-
-  sendChar("1");
-  synthesizeKey("KEY_ArrowDown"); // open
-  let results = await shownPromise;
   checkAutoCompleteResults(results, ["name1"], hostname, "check result deduping for 'name1'");
   synthesizeKey("KEY_ArrowDown"); // first
   synthesizeKey("KEY_Enter");
@@ -132,7 +131,7 @@ add_task(async function test_search() {
 
 add_task(async function test_delete_first_entry() {
   await restoreForm();
-  await openAutocompletePopup();
+  await popupBy();
 
   let index0Promise = notifySelectedIndex(0);
   synthesizeKey("KEY_ArrowDown");
@@ -157,7 +156,7 @@ add_task(async function test_delete_first_entry() {
 
 add_task(async function test_delete_duplicate_entry() {
   await restoreForm();
-  await openAutocompletePopup();
+  await popupBy();
 
   let index0Promise = notifySelectedIndex(0);
   synthesizeKey("KEY_ArrowDown");
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation.html
index ff3ae2e7607b..ee79dfe5ed11 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation.html
@@ -111,7 +111,7 @@ async function promiseACPopupClosed() {
 }
 
 async function showACPopup(formNumber, expectedACLabels) {
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupByArrowDown();
   checkAutoCompleteResults(autocompleteItems, expectedACLabels,
                            window.location.host, "Check all rows are correct");
 }
@@ -202,8 +202,7 @@ add_task(async function test_autofillAutocompletePassword_noGeneration() {
   checkForm(2, "", "pass1");
 
   // No autocomplete results should appear for non-empty pw fields.
-  synthesizeKey("KEY_ArrowDown");
-  await promiseNoUnexpectedPopupShown();
+  await noPopupByArrowDown();
 
   recreateTree(document.getElementById("form2"));
 });
@@ -277,8 +276,7 @@ add_task(async function test_autofillAutocompletePassword_withGeneration() {
     checkForm(formNumber, "", "pass1");
 
     // No autocomplete results should appear for non-empty pw fields.
-    synthesizeKey("KEY_ArrowDown");
-    await promiseNoUnexpectedPopupShown();
+    await noPopupByArrowDown();
 
     info("Removing all logins to test auto-saving of generated passwords");
     await LoginManager.removeAllUserFacingLogins();
@@ -457,7 +455,7 @@ add_task(async function test_deleteAndReselectGeneratedPassword() {
       pword.select();
       synthesizeKey("KEY_Backspace");
     }
-    const autocompleteItems = await openAutocompletePopup();
+    const autocompleteItems = await popupByArrowDown();
     if (index < 0) {
       index = autocompleteItems.length + index;
     }
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_confirm.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_confirm.html
index c0b671942445..f92a4f934fa1 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_confirm.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_confirm.html
@@ -115,11 +115,11 @@ async function promiseACPopupClosed() {
 
 async function fillWithGeneratedPassword(input, expectedResults = ["Use a Securely Generated Password"]) {
   info("Opening the AC menu");
-  const autocompleteItems = await openAutocompletePopup(input);
-  checkAutoCompleteResults(autocompleteItems, expectedResults,
+  const { items } = await openPopupOn(input);
+  checkAutoCompleteResults(items, expectedResults,
     window.location.host, "Check all rows are correct");
 
-  for (let autocompleteItem of autocompleteItems) {
+  for (let autocompleteItem of items) {
     synthesizeKey("KEY_ArrowDown");
     if (autocompleteItem == "Use a Securely Generated Password") {
       synthesizeKey("KEY_Enter");
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_open.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_open.html
index 61eafab0a589..2e2f79652454 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_open.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_open.html
@@ -43,13 +43,10 @@ add_task(async function test_no_autofill() {
 });
 
 add_task(async function test_two_logins() {
-  let shownPromise = promiseACShown();
-  uname.focus();
-  await shownPromise;
+  await popupBy(() => uname.focus());
 
-  shownPromise = promiseACShown();
-  synthesizeKey("KEY_Tab"); // popup on the password field should open upon focus
-  let results = await shownPromise;
+  // popup on the password field should open upon focus
+  let results = await popupBy(() => synthesizeKey("KEY_Tab"));
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
@@ -69,7 +66,7 @@ add_task(async function test_two_logins() {
 add_task(async function test_zero_logins() {
   uname.focus();
 
-  let shownPromise = promiseACShown().then(() => ok(false, "Should not have shown"));
+  let shownPromise = popupBy().then(() => ok(false, "Should not have shown"));
   // Popup on the password field should NOT automatically open upon focus when there are no saved logins.
   synthesizeKey("KEY_Tab"); // focus the password field
   SimpleTest.requestFlakyTimeout("Giving a chance for the unexpected popup to show");
@@ -83,7 +80,7 @@ add_task(async function test_zero_logins() {
 
   checkLoginForm(uname, "", pword, "");
   info("arrow down should still open the popup");
-  autocompleteItems = await openAutocompletePopup();
+  autocompleteItems = await popupByArrowDown();
   checkAutoCompleteResults(autocompleteItems, [], window.location.host, "Check only footer is displayed.");
   checkLoginForm(uname, "", pword, "");
 });
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_sandboxed.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_sandboxed.html
index 112027ecbc25..37b4df02501f 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_sandboxed.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_sandboxed.html
@@ -59,7 +59,7 @@ add_task(async function test_no_autofill() {
 });
 
 add_task(async function test_autocomplete_warning_no_logins() {
-  const autocompleteItems = await openAutocompletePopup(pword);
+  const { items } = await openPopupOn(pword);
 
   let popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
@@ -67,7 +67,7 @@ add_task(async function test_autocomplete_warning_no_logins() {
   let expectedMenuItems = [
     "This connection is not secure. Logins entered here could be compromised. Learn More",
   ];
-  checkAutoCompleteResults(autocompleteItems, expectedMenuItems, hostname, "Check all menuitems are displayed correctly.");
+  checkAutoCompleteResults(items, expectedMenuItems, hostname, "Check all menuitems are displayed correctly.");
 
   checkLoginForm(uname, "", pword, "");
 });
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_tab_between_fields.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_tab_between_fields.html
index b246a576f2fb..4778ef63fff6 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_tab_between_fields.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_tab_between_fields.html
@@ -144,7 +144,7 @@ async function testResultOfTabInteractions(testData) {
   SpecialPowers.wrap(uname).setUserInput("");
 
   info("Placing focus in the password field");
-  const shownPromise = promiseACShown();
+  const shownPromise = popupBy();
   pword.focus();
   await synthesizeKey("KEY_Tab", { shiftKey: true }); // blur pw, focus un
   await new Promise(resolve => SimpleTest.executeSoon(resolve));
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofocus_js.html b/toolkit/components/passwordmgr/test/mochitest/test_autofocus_js.html
index 5677a5964073..9c31fff5587e 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_autofocus_js.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofocus_js.html
@@ -85,11 +85,11 @@ add_task(async function test_reopened_after_edit_not_matching_saved() {
   await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
     this.content.document.getElementById("form-basic-username").value = "nam";
   });
-  let shownPromise = promiseACShown();
-  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
-    this.content.document.getElementById("form-basic-username").focus();
+  await popupBy(async () => {
+    await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+      this.content.document.getElementById("form-basic-username").focus();
+    });
   });
-  await shownPromise;
   await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
     this.content.document.getElementById("form-basic-submit").focus();
   });
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_honor_autocomplete_off.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_honor_autocomplete_off.html
index 7cac3a36a66f..ccb991f2746a 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_honor_autocomplete_off.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_honor_autocomplete_off.html
@@ -86,9 +86,7 @@ async function autoCompleteFieldsFromFirstMatch(form) {
   // trigger autocomplete from the username field
   await SimpleTest.promiseFocus(form.ownerGlobal);
   let uname = form.querySelector("[name='uname']");
-  let shownPromise = promiseACShown();
-  uname.focus();
-  await shownPromise;
+  await popupBy(() => uname.focus());
 
   let formFilled = promiseFormsProcessedInSameProcess();
   await synthesizeKey("KEY_ArrowDown"); // open
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_case_differences.html b/toolkit/components/passwordmgr/test/mochitest/test_case_differences.html
index a063ea0a874c..a162fcd3ab6d 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_case_differences.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_case_differences.html
@@ -59,10 +59,10 @@ add_task(async function test_empty_first_entry() {
   restoreForm();
   let popupState = await getPopupState();
   is(popupState.open, false, "Check popup is initially closed");
-  const autocompleteItems = await openAutocompletePopup();
+  const { items } = await openPopupOn(uname);
   popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected");
-  checkAutoCompleteResults(autocompleteItems, ["name", "Name", "USER"], "example.com", "initial");
+  checkAutoCompleteResults(items, ["name", "Name", "USER"], "example.com", "initial");
 
   // Check first entry
   let index0Promise = notifySelectedIndex(0);
@@ -76,7 +76,7 @@ add_task(async function test_empty_first_entry() {
 
 add_task(async function test_empty_second_entry() {
   restoreForm();
-  await openAutocompletePopup();
+  await openPopupOn(uname);
   synthesizeKey("KEY_ArrowDown"); // first
   synthesizeKey("KEY_ArrowDown"); // second
   synthesizeKey("KEY_Enter");
@@ -86,7 +86,7 @@ add_task(async function test_empty_second_entry() {
 
 add_task(async function test_empty_third_entry() {
   restoreForm();
-  await openAutocompletePopup();
+  await openPopupOn(uname);
   synthesizeKey("KEY_ArrowDown"); // first
   synthesizeKey("KEY_ArrowDown"); // second
   synthesizeKey("KEY_ArrowDown"); // third
@@ -97,8 +97,7 @@ add_task(async function test_empty_third_entry() {
 
 add_task(async function test_preserve_matching_username_case() {
   restoreForm();
-  uname.value = "user";
-  await openAutocompletePopup();
+  await openPopupOn(uname, { inputValue: "user" });
 
   // Check that we don't clobber user-entered text when tabbing away
   // (even with no autocomplete entry selected)
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_insecure_form_field_no_saved_login.html b/toolkit/components/passwordmgr/test/mochitest/test_insecure_form_field_no_saved_login.html
index b098447af838..8fcb9df6f6da 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_insecure_form_field_no_saved_login.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_insecure_form_field_no_saved_login.html
@@ -64,7 +64,7 @@ add_task(async function test_form1_warning_entry() {
   await SimpleTest.promiseFocus(window);
   // Trigger autocomplete popup
   restoreForm();
-  await openAutocompletePopup();
+  await popupBy();
 
   let popupState = await getPopupState();
   is(popupState.open, true, "Check popup is opened");
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_munged_values.html b/toolkit/components/passwordmgr/test/mochitest/test_munged_values.html
index 06f407172952..c14bef003b75 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_munged_values.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_munged_values.html
@@ -266,7 +266,7 @@ add_task(async function test_no_autofill_munged_username_matching_password() {
   });
 
   // we shouldn't get the save password doorhanger...
-  let popupShownPromise = promiseNoUnexpectedPopupShown();
+  let popupShownPromise = noPopupBy();
 
   // Check data sent via PasswordManager:onFormSubmit
   let processedPromise = getSubmitMessage();
@@ -329,7 +329,7 @@ add_task(async function test_autofill_munged_username_matching_password() {
   });
 
   // we shouldn't get the save/update password doorhanger as it didn't change
-  let popupShownPromise =  promiseNoUnexpectedPopupShown();
+  let popupShownPromise = noPopupBy();
 
   // Check data sent via PasswordManager:onFormSubmit
   let processedPromise = getSubmitMessage();
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_password_field_autocomplete.html b/toolkit/components/passwordmgr/test/mochitest/test_password_field_autocomplete.html
index 94dba51b9dda..2db691b1bf2e 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_password_field_autocomplete.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_password_field_autocomplete.html
@@ -107,7 +107,7 @@ async function userOpenAutocompleteOnForm1(autoFillInsecureForms) {
     ["signon.autofillForms.http", autoFillInsecureForms],
   ]});
   await reinitializeForm(1);
-  const autocompleteItems = await openAutocompletePopup();
+  const autocompleteItems = await popupBy();
 
   const popupState = await getPopupState();
   is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_username_focus.html b/toolkit/components/passwordmgr/test/mochitest/test_username_focus.html
index 3d9ccadabb22..cdd71d69ddc7 100644
--- a/toolkit/components/passwordmgr/test/mochitest/test_username_focus.html
+++ b/toolkit/components/passwordmgr/test/mochitest/test_username_focus.html
@@ -113,44 +113,32 @@ add_setup(async () => {
 add_task(async function test_autofilled() {
   let usernameField = getFormElementByName("-autofilled", "uname");
   info("Username and password already filled so don't show autocomplete");
-  let noPopupPromise = promiseNoUnexpectedPopupShown();
-  usernameField.focus();
-  await noPopupPromise;
+  await noPopupBy(() => usernameField.focus());
 
   removeFocus();
   usernameField.value = "testuser";
   info("Focus when we don't have an exact match");
-  let shownPromise = promiseACShown();
-  usernameField.focus();
-  await shownPromise;
+  await popupBy(() => usernameField.focus());
 });
 
 add_task(async function test_autofilled_prefilled_un() {
   let usernameField = getFormElementByName("-autofilled-prefilled-un", "uname");
   info("Username and password already filled so don't show autocomplete");
-  let noPopupPromise = promiseNoUnexpectedPopupShown();
-  usernameField.focus();
-  await noPopupPromise;
+  await noPopupBy(() => usernameField.focus());
 
   removeFocus();
   usernameField.value = "testuser";
   info("Focus when we don't have an exact match");
-  let shownPromise = promiseACShown();
-  usernameField.focus();
-  await shownPromise;
+  await popupBy(() => usernameField.focus());
 });
 
 add_task(async function test_autofilled_focused_dynamic() {
   let usernameField = getFormElementByName("-autofilled-focused-dynamic", "uname");
   let passwordField = getFormElementByName("-autofilled-focused-dynamic", "pword");
   info("Username and password will be filled while username focused");
-  let noPopupPromise = promiseNoUnexpectedPopupShown();
-  usernameField.focus();
-  await noPopupPromise;
+  await noPopupBy(() => usernameField.focus());
   info("triggering autofill");
-  noPopupPromise = promiseNoUnexpectedPopupShown();
-  passwordField.type = "password";
-  await noPopupPromise;
+  await noPopupBy(() => passwordField.type = "password");
 
   let popupState = await getPopupState();
   is(popupState.open, false, "Check popup is closed");
@@ -158,9 +146,7 @@ add_task(async function test_autofilled_focused_dynamic() {
   removeFocus();
   passwordField.value = "test";
   info("Focus when we don't have an exact match");
-  let shownPromise = promiseACShown();
-  usernameField.focus();
-  await shownPromise;
+  await popupBy(() => usernameField.focus());
 });
 
 // Begin testing forms that have multiple saved logins
@@ -168,66 +154,48 @@ add_task(async function test_autofilled_focused_dynamic() {
 add_task(async function test_multiple() {
   let usernameField = getFormElementByName("-multiple", "uname");
   info("Fields not filled due to multiple so autocomplete upon focus");
-  let shownPromise = promiseACShown();
-  usernameField.focus();
-  await shownPromise;
+  await popupBy(() => usernameField.focus());
 });
 
 add_task(async function test_multiple_dynamic() {
   let usernameField = getFormElementByName("-multiple-dynamic", "uname");
   let passwordField = getFormElementByName("-multiple-dynamic", "pword");
   info("Fields not filled but username is focused upon marking so open");
-  let noPopupPromise = promiseNoUnexpectedPopupShown();
-  usernameField.focus();
-  await noPopupPromise;
+  await noPopupBy(() => usernameField.focus());
 
   info("triggering _fillForm code");
-  let shownPromise = promiseACShown();
-  passwordField.type = "password";
-  await shownPromise;
+  await popupBy(() => passwordField.type = "password");
 });
 
 add_task(async function test_multiple_prefilled_un1() {
   let usernameField = getFormElementByName("-multiple-prefilled-un1", "uname");
   info("Username and password already filled so don't show autocomplete");
-  let noPopupPromise = promiseNoUnexpectedPopupShown();
-  usernameField.focus();
-  await noPopupPromise;
+  await noPopupBy(() => usernameField.focus());
 
   removeFocus();
   usernameField.value = "testuser";
   info("Focus when we don't have an exact match");
-  let shownPromise = promiseACShown();
-  usernameField.focus();
-  await shownPromise;
+  await popupBy(() => usernameField.focus());
 });
 
 add_task(async function test_multiple_prefilled_un2() {
   let usernameField = getFormElementByName("-multiple-prefilled-un2", "uname");
   info("Username and password already filled so don't show autocomplete");
-  let noPopupPromise = promiseNoUnexpectedPopupShown();
-  usernameField.focus();
-  await noPopupPromise;
+  await noPopupBy(() => usernameField.focus());
 
   removeFocus();
   usernameField.value = "testuser";
   info("Focus when we don't have an exact match");
-  let shownPromise = promiseACShown();
-  usernameField.focus();
-  await shownPromise;
+  await popupBy(() => usernameField.focus());
 });
 
 add_task(async function test_multiple_prefilled_focused_dynamic() {
   let usernameField = getFormElementByName("-multiple-prefilled-focused-dynamic", "uname");
   let passwordField = getFormElementByName("-multiple-prefilled-focused-dynamic", "pword");
   info("Username and password will be filled while username focused");
-  let noPopupPromise = promiseNoUnexpectedPopupShown();
-  usernameField.focus();
-  await noPopupPromise;
+  await noPopupBy(() => usernameField.focus());
   info("triggering autofill");
-  noPopupPromise = promiseNoUnexpectedPopupShown();
-  passwordField.type = "password";
-  await noPopupPromise;
+  await noPopupBy(() => passwordField.type = "password");
 
   let popupState = await getPopupState();
   is(popupState.open, false, "Check popup is closed");
@@ -235,9 +203,7 @@ add_task(async function test_multiple_prefilled_focused_dynamic() {
   removeFocus();
   passwordField.value = "test";
   info("Focus when we don't have an exact match");
-  let shownPromise = promiseACShown();
-  usernameField.focus();
-  await shownPromise;
+  await popupBy(() => usernameField.focus());
 });
 </script>
 </pre>
diff --git a/toolkit/components/satchel/test/parent_utils.js b/toolkit/components/satchel/test/parent_utils.js
index 2a47cc6ede73..2f07e11444e8 100644
--- a/toolkit/components/satchel/test/parent_utils.js
+++ b/toolkit/components/satchel/test/parent_utils.js
@@ -66,8 +66,8 @@ var ParentUtils = {
     );
   },
 
-  checkRowCount(expectedCount, expectedFirstValue = null) {
-    ContentTaskUtils.waitForCondition(() => {
+  async checkRowCount(expectedCount, expectedFirstValue = null) {
+    await ContentTaskUtils.waitForCondition(() => {
       // This may be called before gAutocompletePopup has initialised
       // which causes it to throw
       try {
@@ -80,23 +80,17 @@ var ParentUtils = {
       } catch (e) {
         return false;
       }
-    }, "Waiting for row count change: " + expectedCount + " First value: " + expectedFirstValue).then(
-      () => {
-        let results = this.getMenuEntries();
-        sendAsyncMessage("gotMenuChange", { results });
-      }
-    );
+    }, `Waiting for row count change to ${expectedCount}, first value: ${expectedFirstValue}.`);
+    return this.getMenuEntries();
   },
 
-  checkSelectedIndex(expectedIndex) {
-    ContentTaskUtils.waitForCondition(() => {
-      return (
+  async checkSelectedIndex(expectedIndex) {
+    await ContentTaskUtils.waitForCondition(
+      () =>
         gAutocompletePopup.popupOpen &&
-        gAutocompletePopup.selectedIndex === expectedIndex
-      );
-    }, "Checking selected index").then(() => {
-      sendAsyncMessage("gotSelectedIndex");
-    });
+        gAutocompletePopup.selectedIndex === expectedIndex,
+      "Checking selected index"
+    );
   },
 
   // Tests using this function need to flip pref for exceptional use of
@@ -175,14 +169,13 @@ addMessageListener("countEntries", ({ name, value }) => {
 
 addMessageListener(
   "waitForMenuChange",
-  ({ expectedCount, expectedFirstValue }) => {
-    ParentUtils.checkRowCount(expectedCount, expectedFirstValue);
-  }
+  ({ expectedCount, expectedFirstValue }) =>
+    ParentUtils.checkRowCount(expectedCount, expectedFirstValue)
 );
 
-addMessageListener("waitForSelectedIndex", ({ expectedIndex }) => {
-  ParentUtils.checkSelectedIndex(expectedIndex);
-});
+addMessageListener("waitForSelectedIndex", ({ expectedIndex }) =>
+  ParentUtils.checkSelectedIndex(expectedIndex)
+);
 addMessageListener("waitForMenuEntryTest", ({ index, statement }) => {
   ParentUtils.testMenuEntry(index, statement);
 });
diff --git a/toolkit/components/satchel/test/satchel_common.js b/toolkit/components/satchel/test/satchel_common.js
index a105013feb58..3b2d8c81efd9 100644
--- a/toolkit/components/satchel/test/satchel_common.js
+++ b/toolkit/components/satchel/test/satchel_common.js
@@ -136,36 +136,16 @@ function updateFormHistory(changes, then = null) {
   });
 }
 
-function notifyMenuChanged(expectedCount, expectedFirstValue, then = null) {
-  return new Promise(resolve => {
-    gChromeScript.sendAsyncMessage("waitForMenuChange", {
-      expectedCount,
-      expectedFirstValue,
-    });
-    gChromeScript.addMessageListener("gotMenuChange", function changed({
-      results,
-    }) {
-      gChromeScript.removeMessageListener("gotMenuChange", changed);
-      gLastAutoCompleteResults = results;
-      if (then) {
-        then(results);
-      }
-      resolve(results);
-    });
-  });
+async function notifyMenuChanged(expectedCount, expectedFirstValue) {
+  gLastAutoCompleteResults = await gChromeScript.sendQuery(
+    "waitForMenuChange",
+    { expectedCount, expectedFirstValue }
+  );
+  return gLastAutoCompleteResults;
 }
 
-function notifySelectedIndex(expectedIndex, then = null) {
-  return new Promise(resolve => {
-    gChromeScript.sendAsyncMessage("waitForSelectedIndex", { expectedIndex });
-    gChromeScript.addMessageListener("gotSelectedIndex", function changed() {
-      gChromeScript.removeMessageListener("gotSelectedIndex", changed);
-      if (then) {
-        then();
-      }
-      resolve();
-    });
-  });
+function notifySelectedIndex(expectedIndex) {
+  return gChromeScript.sendQuery("waitForSelectedIndex", { expectedIndex });
 }
 
 function testMenuEntry(index, statement) {
@@ -202,55 +182,44 @@ function listenForUnexpectedPopupShown() {
   };
 }
 
-async function promiseNoUnexpectedPopupShown() {
-  gPopupShownExpected = false;
-  listenForUnexpectedPopupShown();
-  SimpleTest.requestFlakyTimeout(
-    "Giving a chance for an unexpected popupshown to occur"
-  );
-  await new Promise(resolve => setTimeout(resolve, 1000));
-}
-
-/**
- * Resolve at the next popupshown event for the autocomplete popup
- *
- * @returns {Promise} with the results
- */
-function promiseACShown() {
+async function popupBy(triggerFn) {
   gPopupShownExpected = true;
-  return new Promise(resolve => {
+  const promise = new Promise(resolve => {
     gPopupShownListener = ({ results }) => {
       gPopupShownExpected = false;
       resolve(results);
     };
   });
+  if (triggerFn) {
+    triggerFn();
+  }
+  return promise;
 }
 
-async function popupAfterArrowDown() {
-  const promise = promiseACShown();
-  synthesizeKey("KEY_Escape"); // in case popup is already open
-  synthesizeKey("KEY_ArrowDown");
-  await promise;
+async function noPopupBy(triggerFn) {
+  gPopupShownExpected = false;
+  listenForUnexpectedPopupShown();
+  SimpleTest.requestFlakyTimeout(
+    "Giving a chance for an unexpected popupshown to occur"
+  );
+  if (triggerFn) {
+    await triggerFn();
+  }
+  await new Promise(resolve => setTimeout(resolve, 500));
 }
 
-async function noPopupAfterArrowDown() {
-  const promise = promiseNoUnexpectedPopupShown();
-  synthesizeKey("KEY_Escape"); // in case popup is already open
-  synthesizeKey("KEY_ArrowDown");
-  await promise;
+async function popupByArrowDown() {
+  return popupBy(() => {
+    synthesizeKey("KEY_Escape"); // in case popup is already open
+    synthesizeKey("KEY_ArrowDown");
+  });
 }
 
-/**
- * Open autocomplete popup on a field (if it exists) and wait for it to be shown
- *
- * @param {HTMLInputElement} input - input field to open autocomplete popup on
- * @returns {Promise} of autocomplete items shown
- */
-function openAutocompletePopup(input) {
-  input?.focus();
-  const promisePopupShown = promiseACShown();
-  synthesizeKey("KEY_ArrowDown");
-  return promisePopupShown;
+async function noPopupByArrowDown() {
+  await noPopupBy(() => {
+    synthesizeKey("KEY_Escape"); // in case popup is already open
+    synthesizeKey("KEY_ArrowDown");
+  });
 }
 
 function checkACTelemetryEvent(actualEvent, input, augmentedExtra) {
@@ -346,8 +315,8 @@ async function openPopupOn(
       : inputOrSelector;
   input.value = inputValue;
   input.focus();
-  await (expectPopup ? popupAfterArrowDown() : noPopupAfterArrowDown());
-  return input;
+  const items = await (expectPopup ? popupByArrowDown() : noPopupByArrowDown());
+  return { input, items };
 }
 
 satchelCommonSetup();
diff --git a/toolkit/components/satchel/test/test_bug_511615.html b/toolkit/components/satchel/test/test_bug_511615.html
index 036aa1029e00..2d67c5468b00 100644
--- a/toolkit/components/satchel/test/test_bug_511615.html
+++ b/toolkit/components/satchel/test/test_bug_511615.html
@@ -20,8 +20,7 @@ Test for Form History Autocomplete Untrusted Events: Bug 511615
   </form>
 </div>
 
-<pre id="test">
-<script class="testbody" type="text/javascript">
+<script>
 /**
  * Indicates the time to wait before checking that the state of the autocomplete
  * popup, including whether it is open, has not changed in response to events.
@@ -37,55 +36,33 @@ Test for Form History Autocomplete Untrusted Events: Bug 511615
  */
 const POPUP_RESPONSE_WAIT_TIME_MS = 200;
 
-SimpleTest.requestFlakyTimeout("Must ensure that an event does not happen.");
-
-/**
- * Checks that the popup does not open in response to the given function.
- *
- * @param {Function} triggerFn - function that triggers an event
- * @returns {Promise}
- */
-function expectPopupDoesNotOpen(triggerFn) {
-  const popupShown = promiseACShown();
-  triggerFn();
-  return Promise.race([
-    popupShown.then(() => Promise.reject("Popup opened unexpectedly.")),
-    new Promise(resolve => setTimeout(resolve, POPUP_RESPONSE_WAIT_TIME_MS)),
-  ]);
-}
-
 /**
  * Checks that the selected index in the popup still matches the given value.
  *
  * @param {number} expectedIndex
  * @returns {Promise}
  */
-function checkSelectedIndexAfterResponseTime(expectedIndex) {
-  return new Promise(resolve => {
+async function checkSelectedIndexAfterResponseTime(expectedIndex) {
+  const popupState = await new Promise(resolve => {
     setTimeout(() => getPopupState(resolve), POPUP_RESPONSE_WAIT_TIME_MS);
-  }).then(popupState => {
-    is(popupState.open, true, "Popup should still be open.");
-    is(popupState.selectedIndex, expectedIndex, "Selected index should match.");
   });
+  is(popupState.open, true, "Popup should still be open.");
+  is(popupState.selectedIndex, expectedIndex, "Selected index should match.");
 }
 
-const input = getFormElementByName(1, "field1");
+const input = document.querySelector("#form1 > input");
 
 function doKeyUnprivileged(key) {
-  let keyName = "DOM_VK_" + key.toUpperCase();
+  const keyName = "DOM_VK_" + key.toUpperCase();
   let keycode, charcode, alwaysval;
 
   if (key.length == 1) {
-    keycode = 0;
-    charcode = key.charCodeAt(0);
-    alwaysval = charcode;
+    [keycode, charcode, alwaysval] = [0, key.charCodeAt(0), charcode];
   } else {
-    keycode = KeyEvent[keyName];
+    [keycode, charcode, alwaysval] = [KeyEvent[keyName], 0, keycode];
     if (!keycode) {
       throw new Error("invalid keyname in test");
     }
-    charcode = 0;
-    alwaysval = keycode;
   }
 
   const dnEvent = new KeyboardEvent("keydown", {
@@ -161,13 +138,11 @@ add_task(async function test_untrusted_events_ignored() {
   ]) {
     // We must wait for the entire timeout for each individual test, because the
     // next event in the list might prevent the popup from opening.
-    await expectPopupDoesNotOpen(triggerFn);
+    await noPopupBy(triggerFn);
   }
 
   // A privileged key press will actually open the popup.
-  const promisePopupShown = promiseACShown();
-  synthesizeKey("KEY_ArrowDown");
-  await promisePopupShown;
+  await openPopupOn(input);
 
   // The selected autocomplete item should not change from untrusted events.
   for (let triggerFn of [
@@ -179,7 +154,7 @@ add_task(async function test_untrusted_events_ignored() {
   }
 
   // A privileged key press will actually change the selected index.
-  const indexChanged = new Promise(resolve => notifySelectedIndex(0, resolve));
+  const indexChanged = notifySelectedIndex(0);
   synthesizeKey("KEY_ArrowDown");
   await indexChanged;
 
@@ -198,10 +173,7 @@ add_task(async function test_untrusted_events_ignored() {
     await checkSelectedIndexAfterResponseTime(0);
     is(input.value, "", "The selected item should not have been used.");
   }
-  input.blur(); // Close popup
-
 });
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_bug_787624.html b/toolkit/components/satchel/test/test_bug_787624.html
index 22f4ce610e38..13af53a4770e 100644
--- a/toolkit/components/satchel/test/test_bug_787624.html
+++ b/toolkit/components/satchel/test/test_bug_787624.html
@@ -48,8 +48,7 @@ Form History Layout test: form field autocomplete: Bug 787624
   </div>
 </div>
 
-<pre id="test">
-<script class="testbody" type="text/javascript">
+<script>
 add_setup(async () => {
   await updateFormHistory([
     { op: "remove" },
@@ -59,22 +58,16 @@ add_setup(async () => {
 });
 
 add_task(async function test_popup_not_move_input() {
-  const input = getFormElementByName(1, "field1");
+  const input = document.querySelector("#form1 > input");
   const rect = input.getBoundingClientRect();
-
-  input.focus();
-  const promisePopupShown = promiseACShown();
-  synthesizeKey("KEY_ArrowDown");
-  await promisePopupShown;
-
+  await openPopupOn(input);
   const newRect = input.getBoundingClientRect();
-  is(newRect.left, rect.left,
-     "autocomplete popup does not disturb the input position");
-  is(newRect.top, rect.top,
-     "autocomplete popup does not disturb the input position");
+  isDeeply(
+    [newRect.left, newRect.top],
+    [rect.left, rect.top],
+    "popup does not disturb the input position");
 });
 
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_capture_limit.html b/toolkit/components/satchel/test/test_capture_limit.html
index a2450459042b..859154401624 100644
--- a/toolkit/components/satchel/test/test_capture_limit.html
+++ b/toolkit/components/satchel/test/test_capture_limit.html
@@ -13,8 +13,7 @@
     <button type="submit">Submit</button>
   </form>
 </div>
-<pre id="test">
-<script class="testbody" type="text/javascript">
+<script>
 
 add_setup(async () => {
   const count = await countEntries(null, null);
@@ -58,6 +57,5 @@ add_task(async function captureLimit() {
 });
 
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_datalist_attribute_change.html b/toolkit/components/satchel/test/test_datalist_attribute_change.html
index 8d86f89673be..f9c774f8d0f7 100644
--- a/toolkit/components/satchel/test/test_datalist_attribute_change.html
+++ b/toolkit/components/satchel/test/test_datalist_attribute_change.html
@@ -21,22 +21,16 @@
 
 </div>
 
-<pre id="test">
-<script class="testbody" type="text/javascript">
-
-const { TestUtils } = SpecialPowers.ChromeUtils.import(
-  "resource://testing-common/TestUtils.jsm"
-);
-
-const input = document.getElementById("input");
+<script>
 
 add_task(async function test_dropdown_shown_when_type_attribute_changed() {
+  const input = document.getElementById("input");
   input.addEventListener("click", () => input.setAttribute("type", "text"));
 
   is(input.type, "button", "Input type is initially button.");
 
-  synthesizeMouseAtCenter(input, {button: input, type: "mousedown"}, window);
-  synthesizeMouseAtCenter(input, {button: input, type: "mouseup"}, window);
+  synthesizeMouseAtCenter(input, { button: input, type: "mousedown" }, window);
+  synthesizeMouseAtCenter(input, { button: input, type: "mouseup" }, window);
 
   await SimpleTest.promiseWaitForCondition(() => input.type === "text", "Input type changed to text.");
 
@@ -45,18 +39,15 @@ add_task(async function test_dropdown_shown_when_type_attribute_changed() {
   // We decided to refer fixing this to a later bug,  This is tracked in Bug 1788698.
   // ok(input.matches(":focus-visible"), "Outer focus ring is shown.");
 
-  // We should wait until the next tick/frame, otherwise the popup is not shown.
-  await TestUtils.waitForTick();
-  const promisePopupShown = promiseACShown();
-  synthesizeKey("KEY_ArrowDown");
-  await promisePopupShown;
+  await openPopupOn(input);
 
-  isDeeply(getMenuEntries(), ["Mozilla", "Firefox", "Thunderbird"], "Datalist shown after changing input type from button to text.");
+  isDeeply(
+    getMenuEntries(),
+    ["Mozilla", "Firefox", "Thunderbird"],
+    "Datalist shown after changing input type from button to text.");
   input.removeEventListener("click", () => input.setAttribute("type", "text"));
-
 });
 
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_datalist_dynamic.html b/toolkit/components/satchel/test/test_datalist_dynamic.html
index 9fc3ca0006c6..95fc3eb589de 100644
--- a/toolkit/components/satchel/test/test_datalist_dynamic.html
+++ b/toolkit/components/satchel/test/test_datalist_dynamic.html
@@ -12,11 +12,8 @@
   <option value="ab1">
   <option value="ab2">
 </datalist>
-<pre id="test">
-<script class="testbody">
+<script>
 const { TestUtils } = SpecialPowers.Cu.import("resource://testing-common/TestUtils.jsm");
-const input = document.querySelector("input");
-const datalist = document.querySelector("datalist");
 
 const DATALIST_DATA = {
   "a": ["a1", "a2", "ab1", "ab2"],
@@ -25,16 +22,12 @@ const DATALIST_DATA = {
   "abcd": ["abcd1", "abcd2", "abcde1", "abcde2", "abcde3"]
 };
 
-var resolvePopupShownListener;
-registerPopupShownListener(() => resolvePopupShownListener());
-
-function waitPopup() {
-  return new Promise(resolve => { resolvePopupShownListener = resolve; });
-}
-
 add_task(async function() {
+  const input = document.querySelector("input");
+  const datalist = document.querySelector("datalist");
+
   async function inputHandler() {
-    let options = DATALIST_DATA[input.value] || [];
+    const options = DATALIST_DATA[input.value] || [];
 
     await TestUtils.waitForTick();
 
@@ -42,8 +35,8 @@ add_task(async function() {
       datalist.firstChild.remove();
     }
 
-    for (let option of options) {
-      let element = document.createElement("option");
+    for (const option of options) {
+      const element = document.createElement("option");
       element.setAttribute("value", option);
       datalist.appendChild(element);
     }
@@ -58,9 +51,7 @@ add_task(async function() {
   synthesizeKey("b");
   synthesizeKey("c");
   is(input.value, "abc", "<input>'s value has to be abc for initial data");
-  synthesizeKey("KEY_ArrowDown");
-  await waitPopup();
-
+  await notifyMenuChanged(4);
   let values = getMenuEntries();
   is(values.length, 4, "expected count of datalist popup");
   for (let i = 0; i < values.length; i++) {
@@ -86,5 +77,4 @@ add_task(async function() {
   input.removeEventListener("input", inputHandler);
 });
 </script>
-</pre>
 </html>
diff --git a/toolkit/components/satchel/test/test_datalist_readonly_change.html b/toolkit/components/satchel/test/test_datalist_readonly_change.html
index ab468e8ff6fc..986ef0cb7ee4 100644
--- a/toolkit/components/satchel/test/test_datalist_readonly_change.html
+++ b/toolkit/components/satchel/test/test_datalist_readonly_change.html
@@ -17,20 +17,17 @@
     <option value="Secomundo"></option>
   </datalist>
 <script>
-function oneTick() {
-  return new Promise(resolve => SimpleTest.executeSoon(resolve));
-}
 
 add_task(async function readonly() {
-  let input = await openPopupOn("input", { expectPopup: false });
+  const { input } = await openPopupOn("input", { expectPopup: false });
   ok(input.readOnly, "Input should be readonly");
 
   input.removeAttribute("readonly");
-  await oneTick();
+  await new Promise(resolve => SimpleTest.executeSoon(resolve));
   // AttributeChanged takes control of the input again off a runnable...
   ok(!input.readOnly, "Input should not be readonly");
   is(document.activeElement, input, "Should still be focused");
-  input = await openPopupOn("input");
+  await openPopupOn(input);
   assertAutocompleteItems("First", "Second", "Secomundo");
   assertValueAfterKeys(
     input,
diff --git a/toolkit/components/satchel/test/test_datalist_shadow_dom.html b/toolkit/components/satchel/test/test_datalist_shadow_dom.html
index 1554a76f1804..e2baeccb34f4 100644
--- a/toolkit/components/satchel/test/test_datalist_shadow_dom.html
+++ b/toolkit/components/satchel/test/test_datalist_shadow_dom.html
@@ -29,7 +29,7 @@ host.attachShadow({ mode: "open" }).innerHTML = `
 `;
 
 add_task(async function fill_in_shadow() {
-  const input = await openPopupOn(host.shadowRoot.querySelector("input"));
+  const { input } = await openPopupOn(host.shadowRoot.querySelector("input"));
   assertAutocompleteItems("First", "Second", "Secomundo");
   assertValueAfterKeys(
     input,
@@ -38,7 +38,7 @@ add_task(async function fill_in_shadow() {
 });
 
 add_task(async function filter_and_fill_in_shadow() {
-  const input = await openPopupOn(host.shadowRoot.querySelector("input"));
+  const { input } = await openPopupOn(host.shadowRoot.querySelector("input"));
   sendString("Sec");
   await notifyMenuChanged(2);
   assertAutocompleteItems("Second", "Secomundo");
diff --git a/toolkit/components/satchel/test/test_datalist_with_caching.html b/toolkit/components/satchel/test/test_datalist_with_caching.html
index c0db939e1672..9366d69ff63f 100644
--- a/toolkit/components/satchel/test/test_datalist_with_caching.html
+++ b/toolkit/components/satchel/test/test_datalist_with_caching.html
@@ -36,7 +36,7 @@ add_setup(async () => {
 });
 
 add_task(async function datalist_with_caching() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertAutocompleteItems("Sec", "First", "Second", "Secomundo");
   assertValueAfterKeys(
     input,
@@ -45,7 +45,7 @@ add_task(async function datalist_with_caching() {
 });
 
 add_task(async function filtering_datalist_with_caching() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   sendString("Sec");
   await notifyMenuChanged(3);
   assertAutocompleteItems("Sec", "Second", "Secomundo");
diff --git a/toolkit/components/satchel/test/test_form_autocomplete.html b/toolkit/components/satchel/test/test_form_autocomplete.html
index 112e7f6d9b3d..d18ac0364722 100644
--- a/toolkit/components/satchel/test/test_form_autocomplete.html
+++ b/toolkit/components/satchel/test/test_form_autocomplete.html
@@ -188,7 +188,7 @@ add_setup(async () => {
 });
 
 add_task(async function use_1st_item() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
 
   assertAutocompleteItems("value1", "value2", "value3", "value4");
   assertValueAfterKeys(input, "KEY_ArrowDown", "");
@@ -196,7 +196,7 @@ add_task(async function use_1st_item() {
 });
 
 add_task(async function use_2nd_item() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -204,7 +204,7 @@ add_task(async function use_2nd_item() {
 });
 
 add_task(async function use_3rd_item() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -212,7 +212,7 @@ add_task(async function use_3rd_item() {
 });
 
 add_task(async function use_4th_item() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -220,7 +220,7 @@ add_task(async function use_4th_item() {
 });
 
 add_task(async function use_1st_item_wrap_around() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown",
@@ -229,7 +229,7 @@ add_task(async function use_1st_item_wrap_around() {
 });
 
 add_task(async function use_last_item_via_arrow_up() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowUp", "KEY_Enter"],
@@ -237,7 +237,7 @@ add_task(async function use_last_item_via_arrow_up() {
 });
 
 add_task(async function use_last_item_via_arrow_up_from_selected_1st() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowUp", "KEY_ArrowUp", "KEY_Enter"],
@@ -245,7 +245,7 @@ add_task(async function use_last_item_via_arrow_up_from_selected_1st() {
 });
 
 add_task(async function test9() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowUp", "KEY_ArrowUp", "KEY_ArrowUp", "KEY_ArrowUp",
@@ -254,7 +254,7 @@ add_task(async function test9() {
 });
 
 add_task(async function select_1st_item_without_autocomplete() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowRight"],
@@ -262,7 +262,7 @@ add_task(async function select_1st_item_without_autocomplete() {
 });
 
 add_task(async function set_first_item_without_autocomplete() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowLeft"],
@@ -270,7 +270,7 @@ add_task(async function set_first_item_without_autocomplete() {
 });
 
 add_task(async function use_1st_item_with_page_up() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_PageUp", "KEY_Enter"],
@@ -278,7 +278,7 @@ add_task(async function use_1st_item_with_page_up() {
 });
 
 add_task(async function use_last_item_with_page_down() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_PageDown", "KEY_Enter"],
@@ -288,7 +288,7 @@ add_task(async function use_last_item_with_page_down() {
 add_task(async function delete_1st_item() {
   assertAutocompleteItems("value1", "value2", "value3", "value4");
 
-  const input = await openPopupOn("#form1 input", { inputValue: "value" });
+  const { input } = await openPopupOn("#form1 > input", { inputValue: "value" });
   synthesizeKey("KEY_ArrowDown");
 
   // Tests that on OS X shift-backspace didn't delete the last character
@@ -304,7 +304,7 @@ add_task(async function delete_1st_item() {
 });
 
 add_task(async function use_1st_item_of_3() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -312,7 +312,7 @@ add_task(async function use_1st_item_of_3() {
 });
 
 add_task(async function delete_2nd_item() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   synthesizeKey("KEY_ArrowDown");
   synthesizeKey("KEY_ArrowDown");
   deleteSelectedAutocompleteItem();
@@ -324,7 +324,7 @@ add_task(async function delete_2nd_item() {
 });
 
 add_task(async function use_1st_item_of_2() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -332,7 +332,7 @@ add_task(async function use_1st_item_of_2() {
 });
 
 add_task(async function delete_last_item_of_2() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   synthesizeKey("KEY_ArrowDown");
   synthesizeKey("KEY_ArrowDown");
   deleteSelectedAutocompleteItem();
@@ -344,7 +344,7 @@ add_task(async function delete_last_item_of_2() {
 });
 
 add_task(async function use_1st_item_of_1() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -352,7 +352,7 @@ add_task(async function use_1st_item_of_1() {
 });
 
 add_task(async function delete_only_item() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   synthesizeKey("KEY_ArrowDown");
   deleteSelectedAutocompleteItem();
   await notifyMenuChanged(0);
@@ -361,7 +361,7 @@ add_task(async function delete_only_item() {
 });
 
 add_task(async function form2_fills() {
-  const input = await openPopupOn("#form2 input");
+  const { input } = await openPopupOn("#form2 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -383,7 +383,7 @@ add_task(async function form3_autocomplete_off() {
       resolve();
     }, false);
   });
-  const input = await openPopupOn("#form3 input", { expectPopup: false });
+  const { input } = await openPopupOn("#form3 > input", { expectPopup: false });
   await scroll;
   // Ensure there's no autocomplete dropdown (autocomplete=off is present)
   assertValueAfterKeys(
@@ -393,7 +393,7 @@ add_task(async function form3_autocomplete_off() {
 });
 
 add_task(async function form4_autocomplete_off() {
-  const input = await openPopupOn("#form4 input", { expectPopup: false });
+  const { input } = await openPopupOn("#form4 > input", { expectPopup: false });
   await notifyMenuChanged(0);
 
   // Ensure there's no autocomplete dropdown (autocomplete=off is present)
@@ -404,7 +404,7 @@ add_task(async function form4_autocomplete_off() {
 });
 
 add_task(async function filtering_form5() {
-  const input = await openPopupOn("#form5 input");
+  const { input } = await openPopupOn("#form5 > input");
   sendChar("a");
   await notifyMenuChanged(5);
   assertAutocompleteItems("a", "aa", "aaz", "aa\xe6", "az");
@@ -448,7 +448,7 @@ add_task(async function filtering_form5() {
 });
 
 add_task(async function filtering_form6_part1() {
-  await openPopupOn("#form6 input");
+  await openPopupOn("#form6 > input");
   sendChar("a");
   await notifyMenuChanged(3);
 
@@ -464,7 +464,7 @@ add_task(async function filtering_form6_part1() {
 });
 
 add_task(async function filtering_form6_part2() {
-  await openPopupOn("#form6 input");
+  await openPopupOn("#form6 > input");
   sendChar("b");
   await notifyMenuChanged(1, "bc d\xe6");
   assertAutocompleteItems("bc d\xe6");
@@ -490,27 +490,27 @@ add_task(async function filtering_form6_part2() {
 });
 
 add_task(async function input_maxLength() {
-  let input = await openPopupOn("#form7 input");
+  let { input } = await openPopupOn("#form7 > input");
   await notifyMenuChanged(4);
   assertAutocompleteItems("1", "12", "123", "1234");
 
   input.maxLength = 4;
-  input = await openPopupOn("#form7 input");
+  input = (await openPopupOn("#form7 > input")).input;
   await notifyMenuChanged(4);
   assertAutocompleteItems("1", "12", "123", "1234");
 
   input.maxLength = 3;
-  input = await openPopupOn("#form7 input");
+  input = (await openPopupOn("#form7 > input")).input;
   await notifyMenuChanged(3);
   assertAutocompleteItems("1", "12", "123");
 
   input.maxLength = 2;
-  input = await openPopupOn("#form7 input");
+  input = (await openPopupOn("#form7 > input")).input;
   await notifyMenuChanged(2);
   assertAutocompleteItems("1", "12");
 
   input.maxLength = 1;
-  input = await openPopupOn("#form7 input");
+  input = (await openPopupOn("#form7 > input")).input;
   await notifyMenuChanged(1);
   assertAutocompleteItems("1");
 
@@ -524,21 +524,21 @@ add_task(async function input_maxLength() {
 });
 
 add_task(async function input_maxLength_with_character_typed() {
-  let input = await openPopupOn("#form7 input");
+  let { input } = await openPopupOn("#form7 > input");
   sendChar("1");
   await notifyMenuChanged(4);
   assertAutocompleteItems("1", "12", "123", "1234");
 
   input.maxLength = 3;
-  input = await openPopupOn("#form7 input");
+  input = (await openPopupOn("#form7 > input")).input;
   assertAutocompleteItems("1", "12", "123");
 
   input.maxLength = 2;
-  input = await openPopupOn("#form7 input");
+  input = (await openPopupOn("#form7 > input")).input;
   assertAutocompleteItems("1", "12");
 
   input.maxLength = 1;
-  input = await openPopupOn("#form7 input");
+  input = (await openPopupOn("#form7 > input")).input;
   assertAutocompleteItems("1");
 
   input.maxLength = 0;
@@ -550,14 +550,14 @@ add_task(async function input_maxLength_with_character_typed() {
 
 for (const formId of ["form8", "form9", "form10", "form11"]) {
   add_named_task(formId, async () => {
-    const input = await openPopupOn(`#${formId} input`);
+    const { input } = await openPopupOn(`#${formId} > input`);
     assertAutocompleteItems("value");
     assertValueAfterKeys(input, ["KEY_ArrowDown", "KEY_Enter"], "value");
   });
 }
 
 add_task(async function form12() {
-  const input = await openPopupOn("#form12 input");
+  const { input } = await openPopupOn("#form12 > input");
   assertAutocompleteItems("42");
   assertValueAfterKeys(
     input,
@@ -566,7 +566,7 @@ add_task(async function form12() {
 });
 
 add_task(async function form14() {
-  const input = await openPopupOn("#form14 input", { expectPopup: false });
+  const { input } = await openPopupOn("#form14 > input", { expectPopup: false });
   await notifyMenuChanged(0);
   // type=date with it's own control frame does not have a dropdown menu
   assertAutocompleteItems();
@@ -574,7 +574,7 @@ add_task(async function form14() {
 });
 
 add_task(async function form15() {
-  const input = await openPopupOn("#form15 input", { expectPopup: false });
+  const { input } = await openPopupOn("#form15 > input", { expectPopup: false });
   await notifyMenuChanged(0);
   // type=time with it's own control frame does not have a dropdown menu
   assertAutocompleteItems();
@@ -582,7 +582,7 @@ add_task(async function form15() {
 });
 
 add_task(async function form16() {
-  const input = await openPopupOn("#form16 input", { expectPopup: false });
+  const { input } = await openPopupOn("#form16 > input", { expectPopup: false });
   await notifyMenuChanged(0);
   // type=range does not have a dropdown menu
   assertAutocompleteItems();
@@ -591,7 +591,7 @@ add_task(async function form16() {
 });
 
 add_task(async function form17() {
-  const input = await openPopupOn("#form17 input", { expectPopup: false });
+  const { input } = await openPopupOn("#form17 > input", { expectPopup: false });
   await notifyMenuChanged(0);
   // type=color does not have a dropdown menu
   assertAutocompleteItems();
@@ -600,7 +600,7 @@ add_task(async function form17() {
 });
 
 add_task(async function form18() {
-  const input = await openPopupOn("#form18 input");
+  const { input } = await openPopupOn("#form18 > input");
   assertAutocompleteItems("2016-08");
   assertValueAfterKeys(
     input,
@@ -609,7 +609,7 @@ add_task(async function form18() {
 });
 
 add_task(async function form19() {
-  const input = await openPopupOn("#form19 input");
+  const { input } = await openPopupOn("#form19 > input");
   assertAutocompleteItems("2016-W32");
   assertValueAfterKeys(
     input,
@@ -618,7 +618,7 @@ add_task(async function form19() {
 });
 
 add_task(async function form20() {
-  const input = await openPopupOn("#form20 input", { expectPopup: false });
+  const { input } = await openPopupOn("#form20 > input", { expectPopup: false });
   await notifyMenuChanged(0);
   // type=datetime-local with it's own control frame does not have a dropdown menu
   assertAutocompleteItems();
@@ -627,7 +627,7 @@ add_task(async function form20() {
 
 add_task(async function input_event_fired() {
   await addEntry("field1", "value1");
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
 
   let beforeInputFired = false;
   input.addEventListener("beforeinput", (e) => {
@@ -667,7 +667,7 @@ add_task(async function input_event_fired() {
 });
 
 add_task(async function cancelling_beforeinput_cancels_autocompletion() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   await SpecialPowers.pushPrefEnv({
     set: [["dom.input_event.allow_to_cancel_set_user_input", true]],
   });
@@ -686,7 +686,7 @@ add_task(async function cancelling_beforeinput_cancels_autocompletion() {
 });
 
 add_task(async function no_autocomplete_for_searchbar_history() {
-  await openPopupOn("#form13 input", { expectPopup: false });
+  await openPopupOn("#form13 > input", { expectPopup: false });
   await notifyMenuChanged(0);
   assertAutocompleteItems();
 });
diff --git a/toolkit/components/satchel/test/test_form_autocomplete_validation_at_input_event.html b/toolkit/components/satchel/test/test_form_autocomplete_validation_at_input_event.html
index ae5d6dcbdce8..7df6e97f2770 100644
--- a/toolkit/components/satchel/test/test_form_autocomplete_validation_at_input_event.html
+++ b/toolkit/components/satchel/test/test_form_autocomplete_validation_at_input_event.html
@@ -32,7 +32,7 @@ add_setup(async () => {
 });
 
 add_task(async function input_events() {
-  const input = await openPopupOn("input[name=field1]");
+  const { input } = await openPopupOn("input[name=field1]");
   synthesizeKey("KEY_Escape");
 
   let inputFired = false;
@@ -48,7 +48,7 @@ add_task(async function input_events() {
 });
 
 add_task(async function input_events_for_valid_selection() {
-  const input = await openPopupOn("input[name=field1]");
+  const { input } = await openPopupOn("input[name=field1]");
 
   let inputFired = false;
   input.addEventListener("input", e => {
@@ -63,7 +63,7 @@ add_task(async function input_events_for_valid_selection() {
 });
 
 add_task(async function input_events_for_invalid_selection() {
-  const input = await openPopupOn("input[name=field1]");
+  const { input } = await openPopupOn("input[name=field1]");
 
   let inputFired = false;
   input.addEventListener("input", e => {
diff --git a/toolkit/components/satchel/test/test_form_autocomplete_with_list.html b/toolkit/components/satchel/test/test_form_autocomplete_with_list.html
index ae26b0fb0508..8f77f8e95393 100644
--- a/toolkit/components/satchel/test/test_form_autocomplete_with_list.html
+++ b/toolkit/components/satchel/test/test_form_autocomplete_with_list.html
@@ -83,12 +83,12 @@ add_setup(async () => {
 });
 
 add_task(async function no_changes_when_opening_popup(){
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(input, [], "");
 });
 
 add_task(async function use_1st_entry() {
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertAutocompleteItems("historyvalue", "PASS1", "PASS2", "final");
   assertValueAfterKeys(
     input,
@@ -97,7 +97,7 @@ add_task(async function use_1st_entry() {
 });
 
 add_task(async function use_2nd_entry(){
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -105,7 +105,7 @@ add_task(async function use_2nd_entry(){
 });
 
 add_task(async function use_3rd_entry(){
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -113,7 +113,7 @@ add_task(async function use_3rd_entry(){
 });
 
 add_task(async function use_4th_entry(){
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -121,7 +121,7 @@ add_task(async function use_4th_entry(){
 });
 
 add_task(async function delete_1st_entry(){
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertValueAfterKeys(input, "KEY_ArrowDown", "");
   deleteSelectedAutocompleteItem();
   await notifyMenuChanged(3);
@@ -129,13 +129,13 @@ add_task(async function delete_1st_entry(){
 });
 
 add_task(async function can_use_next_item_after_deletion(){
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   assertAutocompleteItems("PASS1", "PASS2", "final");
   assertValueAfterKeys(input, ["KEY_ArrowDown", "KEY_Enter"], "Google");
 });
 
 add_task(async function autocomplete_on_datalist_with_cached_results(){
-  const input = await openPopupOn("#form1 input");
+  const { input } = await openPopupOn("#form1 > input");
   sendString("PAS");
   await notifyMenuChanged(2);
   sendString("S1");
@@ -147,7 +147,7 @@ add_task(async function autocomplete_on_datalist_with_cached_results(){
 });
 
 add_task(async function fills_with_autocomplete_off_on_form(){
-  const input = await openPopupOn("#form4 input");
+  const { input } = await openPopupOn("#form4 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -156,7 +156,7 @@ add_task(async function fills_with_autocomplete_off_on_form(){
 });
 
 add_task(async function use_1st_entry_with_autocomplete_off_on_form(){
-  const input = await openPopupOn("#form4 input");
+  const { input } = await openPopupOn("#form4 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -164,7 +164,7 @@ add_task(async function use_1st_entry_with_autocomplete_off_on_form(){
 });
 
 add_task(async function use_2nd_entry_with_autocomplete_off_on_form(){
-  const input = await openPopupOn("#form4 input");
+  const { input } = await openPopupOn("#form4 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -172,7 +172,7 @@ add_task(async function use_2nd_entry_with_autocomplete_off_on_form(){
 });
 
 add_task(async function use_3rd_entry_with_autocomplete_off_on_form(){
-  const input = await openPopupOn("#form4 input");
+  const { input } = await openPopupOn("#form4 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -180,7 +180,7 @@ add_task(async function use_3rd_entry_with_autocomplete_off_on_form(){
 });
 
 add_task(async function fills_with_autocomplete_off_on_input(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -189,7 +189,7 @@ add_task(async function fills_with_autocomplete_off_on_input(){
 });
 
 add_task(async function use_1st_entry_with_autocomplete_off_on_input(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -197,7 +197,7 @@ add_task(async function use_1st_entry_with_autocomplete_off_on_input(){
 });
 
 add_task(async function use_2nd_entry_with_autocomplete_off_on_input(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -205,7 +205,7 @@ add_task(async function use_2nd_entry_with_autocomplete_off_on_input(){
 });
 
 add_task(async function use_3rd_entry_with_autocomplete_off_on_input(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_ArrowDown", "KEY_ArrowDown", "KEY_Enter"],
@@ -218,7 +218,7 @@ add_task(async function remove_item_from_datalist(){
   //
   // Removing the second element while on the first then going down and
   // push enter. Value should be one from the third suggesion.
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   synthesizeKey("KEY_ArrowDown");
   const datalist = document.getElementById("suggest");
   const toRemove = datalist.children[1];
@@ -234,7 +234,7 @@ add_task(async function remove_item_from_datalist(){
 });
 
 add_task(async function add_item_to_datalist(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   const datalist = document.getElementById("suggest");
 
   // Adding an attribute after the first one while on the first then going
@@ -256,10 +256,10 @@ add_task(async function change_datalist_option_value(){
   await notifyMenuChanged(0);
 
   // Change the first element value attribute.
-  let prevValue = datalist.children[0].value;
+  const prevValue = datalist.children[0].value;
   datalist.children[0].value = "foo";
 
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   assertValueAfterKeys(
     input,
     ["KEY_ArrowDown", "KEY_Enter"],
@@ -274,7 +274,7 @@ add_task(async function change_datalist_option_text_content(){
   const prevValue = datalist.children[0].getAttribute("value");
   datalist.children[0].removeAttribute("value");
   datalist.children[0].textContent = "foobar";
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
 
   assertValueAfterKeys(
     input,
@@ -286,7 +286,7 @@ add_task(async function change_datalist_option_text_content(){
 });
 
 add_task(async function filters_with_1st_letter(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   sendString("f");
   assertValueAfterKeys(
     input,
@@ -295,7 +295,7 @@ add_task(async function filters_with_1st_letter(){
 });
 
 add_task(async function filters_with_letter_in_the_middle(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   sendString("in");
   assertValueAfterKeys(
     input,
@@ -304,7 +304,7 @@ add_task(async function filters_with_letter_in_the_middle(){
 });
 
 add_task(async function no_filtering_when_mozNoFilter(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   input.setAttribute("mozNoFilter", "true");
   sendString("f");
   await notifyMenuChanged(3);
@@ -316,7 +316,7 @@ add_task(async function no_filtering_when_mozNoFilter(){
 });
 
 add_task(async function input_events(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
 
   let beforeInputFired = false;
   input.addEventListener("beforeinput", (event) => {
@@ -352,7 +352,7 @@ add_task(async function input_events(){
 });
 
 add_task(async function cancelled_beforeinput_event(){
-  const input = await openPopupOn("#form3 input");
+  const { input } = await openPopupOn("#form3 > input");
   await SpecialPowers.pushPrefEnv({
     set: [["dom.input_event.allow_to_cancel_set_user_input", true]],
   });
@@ -371,7 +371,7 @@ add_task(async function cancelled_beforeinput_event(){
 });
 
 add_task(async function attempt_to_delete_datalist_entries(){
-  const input = await openPopupOn("#form5 input");
+  const { input } = await openPopupOn("#form5 > input");
   assertAutocompleteItems("history1", "history2", "PASS1", "PASS2", "final");
 
   assertValueAfterKeys(
@@ -405,7 +405,7 @@ for (const input of document
     async () => {
       input.focus();
       is(document.activeElement, input, "Input is focused.");
-      await (expectPopup ? popupAfterArrowDown() : noPopupAfterArrowDown());
+      await (expectPopup ? popupByArrowDown() : noPopupByArrowDown());
     }
   );
 }
diff --git a/toolkit/components/satchel/test/test_form_submission.html b/toolkit/components/satchel/test/test_form_submission.html
index 18b913d3193a..d1c0542609c1 100644
--- a/toolkit/components/satchel/test/test_form_submission.html
+++ b/toolkit/components/satchel/test/test_form_submission.html
@@ -263,8 +263,7 @@
   </form>
 
 </div>
-<pre id="test">
-<script class="testbody" type="text/javascript">
+<script>
 /* eslint-disable complexity */
 
 const ccNumbers = {
@@ -352,11 +351,7 @@ async function checkSubmitSaves(formNumber, inputName, interactiveValue, savedVa
   is(historyEntriesCount, 1, form.getAttribute("purpose"));
 }
 
-// This will prevent endless loop of tests
-for (const form of document.forms) {
-  /* eslint-disable-next-line mozilla/balanced-listeners */
-  form.addEventListener("submit", e => e.preventDefault());
-}
+preventSubmitOnForms();
 
 add_setup(async () => {
   await updateFormHistory([
@@ -403,7 +398,7 @@ add_task(async function form7_does_not_save() {
 
 add_task(async function form8_does_not_save() {
   // Form 8 has an input with no name or input attribute.
-  let input = SpecialPowers.wrap(document.getElementById("form8").elements[0]);
+  const input = SpecialPowers.wrap(document.getElementById("form8").elements[0]);
   is(input.type, "text", "checking we got unidentified input");
   input.setUserInput("dontSaveThis");
   await checkSubmitDoesNotSave(8);
@@ -443,7 +438,7 @@ add_task(async function form13_does_not_save() {
 });
 
 add_task(async function form14_does_not_save() {
-  let input = SpecialPowers.wrap(document.getElementById("form14").elements[0]);
+  const input = SpecialPowers.wrap(document.getElementById("form14").elements[0]);
   input.type  = "password";
   input.setUserInput("dontSaveThis");
   // Set it back to type=text to simulate a password visibility toggle.
@@ -599,6 +594,5 @@ add_task(async function form109_saves() {
 });
 
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_history_datalist_duplicates.html b/toolkit/components/satchel/test/test_history_datalist_duplicates.html
index a4641ad6a274..395405396ae5 100644
--- a/toolkit/components/satchel/test/test_history_datalist_duplicates.html
+++ b/toolkit/components/satchel/test/test_history_datalist_duplicates.html
@@ -12,7 +12,7 @@
 
   <!-- normal, basic form -->
   <form id="form1" onsubmit="return false;">
-    <input   list="suggest" type="text" name="field1" id="field1">
+    <input list="suggest" type="text" name="field1" id="field1">
     <button type="submit">Submit</button>
     <datalist id="suggest">
       <option value="Mozilla">
@@ -23,46 +23,33 @@
 
 </div>
 
-<pre id="test">
-<script class="testbody" type="text/javascript">
-const input = document.getElementById("field1");
+<script>
 
 add_setup(async () => {
-  await new Promise(resolve => updateFormHistory([
+  await updateFormHistory([
     { op: "add", fieldname: "field1", value: "Mozilla" },
     { op: "add", fieldname: "field1", value: "Firefox" },
     { op: "add", fieldname: "field1", value: "Relay" },
-  ], resolve));
+  ]);
 });
 
-
 add_task(async function test_all_entries_are_unique_and_ordered() {
-    await triggerAutofillAndCheckEntriesValue("",["Relay", "Mozilla", "Firefox", "Relay is awesome"]);
+  await triggerAutofillAndCheckEntriesValue("",["Relay", "Mozilla", "Firefox", "Relay is awesome"]);
 });
 
 add_task(async function test_duplicate_entries_are_shown_once() {
-    await triggerAutofillAndCheckEntriesValue("f", ["Firefox"]);
+  await triggerAutofillAndCheckEntriesValue("f", ["Firefox"]);
 });
 
 add_task(async function test_non_duplicate_entries_are_shown_once() {
-    await triggerAutofillAndCheckEntriesValue("rel",["Relay", "Relay is awesome"]);
+  await triggerAutofillAndCheckEntriesValue("rel",["Relay", "Relay is awesome"]);
 });
 
-
-
-
 async function triggerAutofillAndCheckEntriesValue(inputValue, expectedValues) {
-  SpecialPowers.wrap(input).setUserInput(inputValue);
-  input.focus();
-  const promisePopupShown = promiseACShown();
-  synthesizeKey("KEY_ArrowDown");
-  await promisePopupShown;
+  await openPopupOn("#form1 > input", { inputValue });
   isDeeply(getMenuEntries(), expectedValues, "Matching deduplicated autocomplete list entries with expected values.");
-  input.blur(); // Close popup
-
 }
 
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_input_valid_state_with_autocomplete.html b/toolkit/components/satchel/test/test_input_valid_state_with_autocomplete.html
index 8e9b47ad8047..196ca5976584 100644
--- a/toolkit/components/satchel/test/test_input_valid_state_with_autocomplete.html
+++ b/toolkit/components/satchel/test/test_input_valid_state_with_autocomplete.html
@@ -35,7 +35,7 @@ add_setup(async () => {
 
 add_task(async function datalist_with_caching() {
    const kSetUserInputCancelable = SpecialPowers.getBoolPref("dom.input_event.allow_to_cancel_set_user_input");
-   const input = await openPopupOn("input[name=field1]");
+   const { input } = await openPopupOn("input[name=field1]");
    synthesizeKey("KEY_Escape");
 
    let beforeInputFired = false;
@@ -60,7 +60,7 @@ add_task(async function datalist_with_caching() {
    ok(beforeInputFired, "'beforeinput' event fired at typing 'e'");
    ok(inputFired, "'input' event fired at typing 'e'");
 
-   await promiseACShown();
+   await notifyMenuChanged(2);
    inputFired = false;
    beforeInputFired = false;
    input.addEventListener("beforeinput", e => {
@@ -91,7 +91,7 @@ add_task(async function datalist_with_caching() {
    inputFired = false;
    beforeInputFired = false;
    synthesizeKey("KEY_Backspace");
-   await promiseACShown();
+   await notifyMenuChanged(2);
    synthesizeKey("KEY_ArrowDown");
    synthesizeKey("KEY_ArrowDown");
    input.addEventListener("beforeinput", e => {
diff --git a/toolkit/components/satchel/test/test_password_autocomplete.html b/toolkit/components/satchel/test/test_password_autocomplete.html
index 39d19890504f..d24f556d9ec9 100644
--- a/toolkit/components/satchel/test/test_password_autocomplete.html
+++ b/toolkit/components/satchel/test/test_password_autocomplete.html
@@ -32,39 +32,7 @@
   </form>
 </div>
 
-<pre id="test">
-<script class="testbody" type="text/javascript">
-/**
- * Indicates the time to wait before checking that the state of the autocomplete
- * popup, including whether it is open, has not changed in response to events.
- *
- * Manual testing on a fast machine revealed that 80ms was still unreliable,
- * while 100ms detected a simulated failure reliably. Unfortunately, this means
- * that to take into account slower machines we should use a larger value.
- *
- * Note that if a machine takes more than this time to show the popup, this
- * would not cause a failure, conversely the machine would not be able to detect
- * whether the test should have failed. In other words, this use of timeouts is
- * never expected to cause intermittent failures with test automation.
- */
-const POPUP_RESPONSE_WAIT_TIME_MS = 200;
-
-SimpleTest.requestFlakyTimeout("Must ensure that an event does not happen.");
-
-/**
- * Checks that the popup does not open in response to the given function.
- *
- * @param {Function} triggerFn - function that triggers an event
- * @returns {Promise}
- */
-function expectPopupDoesNotOpen(triggerFn) {
-  const popupShown = promiseACShown();
-  triggerFn();
-  return Promise.race([
-    popupShown.then(() => Promise.reject("Popup opened unexpectedly.")),
-    new Promise(resolve => setTimeout(resolve, POPUP_RESPONSE_WAIT_TIME_MS)),
-  ]);
-}
+<script>
 
 add_setup(async () => {
   await SpecialPowers.pushPrefEnv({set: [["signon.rememberSignons", false]]});
@@ -72,10 +40,10 @@ add_setup(async () => {
   is(window.location.protocol, "https:", "This test must run on HTTPS");
 
   // Now that rememberSignons is false, create the password fields.
-  getFormElementByName(1, "field1").type = "password";
-  getFormElementByName(2, "field1").type = "password";
+  document.querySelector("#form1 > input").type = "password";
+  document.querySelector("#form2 > input").type = "password";
 
-  await new Promise(resolve => updateFormHistory([
+  await updateFormHistory([
     { op: "remove" },
     { op: "add", fieldname: "field1", value: "value1" },
     { op: "add", fieldname: "field1", value: "value2" },
@@ -86,11 +54,11 @@ add_setup(async () => {
     { op: "add", fieldname: "field1", value: "value7" },
     { op: "add", fieldname: "field1", value: "value8" },
     { op: "add", fieldname: "field1", value: "value9" },
-  ], resolve));
+  ]);
 });
 
 add_task(async function test_secure_noFormHistoryOrWarning() {
-  const input = getFormElementByName(1, "field1");
+  const input = document.querySelector("#form1 input");
 
   // The autocomplete popup should not open under any circumstances on
   // type=password with password manager disabled.
@@ -103,30 +71,19 @@ add_task(async function test_secure_noFormHistoryOrWarning() {
     () => sendString("v "),
     () => synthesizeKey("KEY_Backspace"),
   ]) {
-    ok(true, "Testing: " + triggerFn.toString());
+    info("Testing: " + triggerFn.toString());
     // We must wait for the entire timeout for each individual test, because the
     // next event in the list might prevent the popup from opening.
-    await expectPopupDoesNotOpen(triggerFn);
+    await noPopupBy(triggerFn);
   }
-
-  input.blur();
 });
 
 add_task(async function test_insecure_focusWarning() {
   // Form 2 has an insecure action so should show the warning even if password manager is disabled.
-  const input = getFormElementByName(2, "field1");
-
-  input.focus();
-  const promisePopupShown = promiseACShown();
-  synthesizeKey("KEY_ArrowDown");
-  await promisePopupShown;
-
+  await openPopupOn("#form2 > input");
   ok(getMenuEntries()[0].includes("Logins entered here could be compromised"),
      "Check warning is first");
-
-  input.blur(); // Close popup.
 });
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_popup_direction.html b/toolkit/components/satchel/test/test_popup_direction.html
index 59bbcddc17b4..6b2fa010d651 100644
--- a/toolkit/components/satchel/test/test_popup_direction.html
+++ b/toolkit/components/satchel/test/test_popup_direction.html
@@ -20,8 +20,7 @@ Test for Popup Direction
   </form>
 </div>
 
-<pre id="test">
-<script class="testbody" type="text/javascript">
+<script>
 
 add_setup(async () => {
   await updateFormHistory([
@@ -32,22 +31,14 @@ add_setup(async () => {
 });
 
 add_task(async function test_popup_direction() {
-  let input = getFormElementByName(1, "field1");
-
-  for (let direction of ["ltr", "rtl"]) {
+  for (const direction of ["ltr", "rtl"]) {
     document.getElementById("content").style.direction = direction;
-
-    await openAutocompletePopup(input);
-
-    let popupState = await getPopupState();
+    await openPopupOn("#form1 > input");
+    const popupState = await getPopupState();
     is(popupState.direction, direction, "Direction should match.");
-
-    // Close the popup.
-    input.blur();
   }
 });
 
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_popup_enter_event.html b/toolkit/components/satchel/test/test_popup_enter_event.html
index c33c945a42fb..6150a8a57abf 100644
--- a/toolkit/components/satchel/test/test_popup_enter_event.html
+++ b/toolkit/components/satchel/test/test_popup_enter_event.html
@@ -19,11 +19,7 @@ Form History test: Test for events while the form history popup is open
   </form>
 </div>
 
-<pre id="test">
-<script class="testbody">
-var form = document.getElementById("form1");
-var input = getFormElementByName(1, "field1");
-var expectedValue = "value1";
+<script>
 
 add_setup(async () => {
   await updateFormHistory([
@@ -32,43 +28,37 @@ add_setup(async () => {
   ]);
 });
 
-function handleEnter(evt) {
-  if (evt.keyCode != KeyEvent.DOM_VK_RETURN) {
-    return;
-  }
-
-  info("RETURN received for phase: " + evt.eventPhase);
-  if (input.value == expectedValue) {
-    ok(true, "RETURN should be received when the popup is closed");
-    is(input.value, expectedValue, "Check input value when enter is pressed the 2nd time");
-    info("form should submit with the default handler");
-  } else {
-    ok(false, "RETURN keypress shouldn't have been received when a popup item is selected");
-  }
-}
-
 add_task(async function popupEnterEvent() {
+  const form = document.querySelector("#form1");
+  const input = form.querySelector("input");
+  const expectedValue = "value1";
+
+  function handleEnter(e) {
+    if (e.keyCode != KeyEvent.DOM_VK_RETURN) {
+      return;
+    }
+
+    info("RETURN received for phase: " + e.eventPhase);
+    if (input.value == expectedValue) {
+      ok(true, "RETURN should be received when the popup is closed");
+      is(input.value, expectedValue, "Check input value when enter is pressed the 2nd time");
+      info("form should submit with the default handler");
+    } else {
+      ok(false, "RETURN keypress shouldn't have been received when a popup item is selected");
+    }
+  }
+
   const submitTested = new Promise(resolve => {
     SpecialPowers.addSystemEventListener(input, "keypress", handleEnter, true);
-    form.addEventListener("submit", evt => {
-      evt.preventDefault();
-
+    form.addEventListener("submit", e => {
+      e.preventDefault();
       is(input.value, expectedValue, "Check input value in the submit handler");
-
       SpecialPowers.removeSystemEventListener(input, "keypress", handleEnter, true);
-
       resolve();
     }, { once: true });
   });
-  const autocompleteShown = promiseACShown();
 
-  // Focus the input before adjusting.value so that the caret goes to the end
-  // (since OS X doesn't show the dropdown otherwise).
-  input.focus();
-  input.value = "value";
-  input.focus();
-  synthesizeKey("KEY_ArrowDown");
-  await autocompleteShown;
+  await openPopupOn(input, { inputValue: "value" });
   synthesizeKey("KEY_ArrowDown");
   synthesizeKey("KEY_Enter"); // select the first entry in the popup
   synthesizeKey("KEY_Enter"); // try to submit the form with the filled value
@@ -76,6 +66,5 @@ add_task(async function popupEnterEvent() {
 });
 
 </script>
-</pre>
 </body>
 </html>
diff --git a/toolkit/components/satchel/test/test_submit_on_keydown_enter.html b/toolkit/components/satchel/test/test_submit_on_keydown_enter.html
index 833bdfb9eba5..f5879a2b5ef1 100644
--- a/toolkit/components/satchel/test/test_submit_on_keydown_enter.html
+++ b/toolkit/components/satchel/test/test_submit_on_keydown_enter.html
@@ -19,12 +19,7 @@ Form History test: Test for keydown handler submitting the form
   </form>
 </div>
 
-<pre id="test">
-<script class="testbody">
-var form = document.getElementById("form1");
-var input = getFormElementByName(1, "field1");
-var expectedValue = "value1";
-var beforeInputFired = false;
+<script>
 
 add_setup(async () => {
    await updateFormHistory([
@@ -34,6 +29,10 @@ add_setup(async () => {
 });
 
 add_task(async function submitOnKeydownEnter() {
+   const form = document.querySelector("#form1");
+   const input = form.querySelector("input");
+   const expectedValue = "value1";
+   let beforeInputFired = false;
    const submitTested = new Promise(resolve => {
 
       function handleBeforeInput(aEvent) {
@@ -56,23 +55,18 @@ add_task(async function submitOnKeydownEnter() {
             'getTargetRanges() of "beforeinput" event should return empty array');
       }
 
-      function handleInput(aEvent) {
+      function handleInput(e) {
          info("Input");
          ok(beforeInputFired, '"beforeinput" event should have been fired');
          is(input.value, expectedValue, "Check input value");
-         ok(aEvent instanceof InputEvent,
+         ok(e instanceof InputEvent,
             '"input" event should be dispatched with InputEvent interface');
-         is(aEvent.cancelable, false,
-            '"input" event should be never cancelable');
-         is(aEvent.bubbles, true,
-            '"input" event should always bubble');
-         is(aEvent.inputType, "insertReplacementText",
-            'inputType of "input" event should be "insertReplacementText"');
-         is(aEvent.data, expectedValue,
-            `data of "input" event should be "${expectedValue}"`);
-         is(aEvent.dataTransfer, null,
-            'dataTransfer of "input" event should be null');
-         is(aEvent.getTargetRanges().length, 0,
+         is(e.cancelable, false, '"input" event should be never cancelable');
+         is(e.bubbles, true, '"input" event should always bubble');
+         is(e.inputType, "insertReplacementText", 'inputType of "input" event');
+         is(e.data, expectedValue, "data of input event");
+         is(e.dataTransfer, null, 'dataTransfer of "input" event');
+         is(e.getTargetRanges().length, 0,
             'getTargetRanges() of "input" event should return empty array');
          removeEventListeners();
          resolve();
@@ -101,16 +95,7 @@ add_task(async function submitOnKeydownEnter() {
       }, { once: true });
    });
 
-   const autocompleteShown = promiseACShown();
-
-   // Focus the input before adjusting.value so that the caret goes to the end
-   // (since OS X doesn't show the dropdown otherwise).
-   input.focus();
-   input.value = "value";
-   input.focus();
-   synthesizeKey("KEY_ArrowDown");
-
-   await autocompleteShown;
+   await openPopupOn(input, { inputValue: "value" });
 
    synthesizeKey("KEY_ArrowDown");
    synthesizeKey("KEY_Enter"); // select the first entry in the popup
@@ -119,6 +104,5 @@ add_task(async function submitOnKeydownEnter() {
 });
 
 </script>
-</pre>
 </body>
 </html>