diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-01.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-01.js
index 3995fcbdfb4e..ce59e92d75ee 100644
--- a/browser/devtools/debugger/test/browser_dbg_blackboxing-01.js
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-01.js
@@ -5,72 +5,52 @@
  * Test that if we black box a source and then refresh, it is still black boxed.
  */
 
-const TAB_URL = EXAMPLE_URL + "binary_search.html";
+const TAB_URL = EXAMPLE_URL + "doc_binary_search.html";
 
-var gPane = null;
-var gTab = null;
-var gDebuggee = null;
-var gDebugger = null;
+let gTab, gDebuggee, gPanel, gDebugger;
 
-function test()
-{
-  let scriptShown = false;
-  let framesAdded = false;
-  let resumed = false;
-  let testStarted = false;
-
-  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
-    resumed = true;
+function test() {
+  initDebugger(TAB_URL).then(([aTab, aDebuggee, aPanel]) => {
     gTab = aTab;
     gDebuggee = aDebuggee;
-    gPane = aPane;
-    gDebugger = gPane.panelWin;
+    gPanel = aPanel;
+    gDebugger = gPanel.panelWin;
 
-    testBlackBoxSource();
+    waitForSourceShown(gPanel, ".coffee")
+      .then(testBlackBoxSource)
+      .then(testBlackBoxReload)
+      .then(() => closeDebuggerAndFinish(gPanel))
+      .then(null, aError => {
+        ok(false, "Got an error: " + aError.message + "\n" + aError.stack);
+      });
   });
 }
 
 function testBlackBoxSource() {
-  once(gDebugger, "Debugger:SourceShown", function () {
-    const checkbox = gDebugger.document.querySelector(".side-menu-widget-item-checkbox");
-    ok(checkbox, "Should get the checkbox for black boxing the source");
-    ok(checkbox.checked, "Should not be black boxed by default");
+  const checkbox = gDebugger.document.querySelector(".side-menu-widget-item-checkbox");
+  ok(checkbox, "Should get the checkbox for black boxing the source.");
+  ok(checkbox.checked, "Should not be black boxed by default.");
 
-    const { activeThread } = gDebugger.DebuggerController;
-    activeThread.addOneTimeListener("blackboxchange", function (event, sourceClient) {
-      ok(sourceClient.isBlackBoxed, "The source should be black boxed now");
-      ok(!checkbox.checked, "The checkbox should no longer be checked.");
-
-      testBlackBoxReload();
-    });
-
-    checkbox.click();
+  let finished = waitForThreadEvents(gPanel, "blackboxchange").then(aSource => {
+    ok(aSource.isBlackBoxed, "The source should be black boxed now.");
+    ok(!checkbox.checked, "The checkbox should no longer be checked.");
   });
+
+  checkbox.click();
+  return finished;
 }
 
 function testBlackBoxReload() {
-  once(gDebugger, "Debugger:SourceShown", function () {
+  return reloadActiveTab(gPanel, gDebugger.EVENTS.SOURCE_SHOWN).then(() => {
     const checkbox = gDebugger.document.querySelector(".side-menu-widget-item-checkbox");
-    ok(checkbox, "Should get the checkbox for black boxing the source");
-    ok(!checkbox.checked, "Should still be black boxed");
-
-    closeDebuggerAndFinish();
+    ok(checkbox, "Should get the checkbox for black boxing the source.");
+    ok(!checkbox.checked, "Should still be black boxed.");
   });
-
-  gDebuggee.location.reload();
-}
-
-function once(target, event, callback) {
-  target.addEventListener(event, function _listener(...args) {
-    target.removeEventListener(event, _listener, false);
-    callback.apply(null, args);
-  }, false);
 }
 
 registerCleanupFunction(function() {
-  removeTab(gTab);
-  gPane = null;
   gTab = null;
   gDebuggee = null;
+  gPanel = null;
   gDebugger = null;
 });
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-02.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-02.js
index 44169e90e2ef..9c44ff27c854 100644
--- a/browser/devtools/debugger/test/browser_dbg_blackboxing-02.js
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-02.js
@@ -6,82 +6,63 @@
  * view.
  */
 
-const TAB_URL = EXAMPLE_URL + "browser_dbg_blackboxing.html";
-const BLACKBOXME_URL = EXAMPLE_URL + "blackboxing_blackboxme.js"
+const TAB_URL = EXAMPLE_URL + "doc_blackboxing.html";
+const BLACKBOXME_URL = EXAMPLE_URL + "code_blackboxing_blackboxme.js"
 
-var gPane = null;
-var gTab = null;
-var gDebuggee = null;
-var gDebugger = null;
+let gTab, gDebuggee, gPanel, gDebugger;
+let gFrames;
 
-function test()
-{
-  let scriptShown = false;
-  let framesAdded = false;
-  let resumed = false;
-  let testStarted = false;
-
-  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
-    resumed = true;
+function test() {
+  initDebugger(TAB_URL).then(([aTab, aDebuggee, aPanel]) => {
     gTab = aTab;
     gDebuggee = aDebuggee;
-    gPane = aPane;
-    gDebugger = gPane.panelWin;
+    gPanel = aPanel;
+    gDebugger = gPanel.panelWin;
+    gFrames = gDebugger.DebuggerView.StackFrames;
 
-    testBlackBoxSource();
+    waitForSourceShown(gPanel, BLACKBOXME_URL)
+      .then(testBlackBoxSource)
+      .then(testBlackBoxStack)
+      .then(() => resumeDebuggerThenCloseAndFinish(gPanel))
+      .then(null, aError => {
+        ok(false, "Got an error: " + aError.message + "\n" + aError.stack);
+      });
   });
 }
 
 function testBlackBoxSource() {
-  once(gDebugger, "Debugger:SourceShown", function () {
-    const checkbox = getBlackBoxCheckbox(BLACKBOXME_URL);
-    ok(checkbox, "Should get the checkbox for blackBoxing the source");
-
-    const { activeThread } = gDebugger.DebuggerController;
-    activeThread.addOneTimeListener("blackboxchange", function (event, sourceClient) {
-      ok(sourceClient.isBlackBoxed, "The source should be black boxed now");
-
-      testBlackBoxStack();
-    });
-
-    checkbox.click();
+  let finished = waitForThreadEvents(gPanel, "blackboxchange").then(aSource => {
+    ok(aSource.isBlackBoxed, "The source should be black boxed now.");
   });
+
+  getBlackBoxCheckbox(BLACKBOXME_URL).click();
+  return finished;
 }
 
 function testBlackBoxStack() {
-  const { activeThread } = gDebugger.DebuggerController;
-  activeThread.addOneTimeListener("framesadded", function () {
-    const frames = gDebugger.DebuggerView.StackFrames.widget._list;
-
-    is(frames.querySelectorAll(".dbg-stackframe").length, 3,
-       "Should only get 3 frames");
-
-    is(frames.querySelectorAll(".dbg-stackframe-black-boxed").length, 1,
-       "And one of them should be the combined black boxed frames");
-
-    closeDebuggerAndFinish();
+  let finished = waitForSourceAndCaretAndScopes(gPanel, ".html", 21).then(() => {
+    is(gFrames.itemCount, 3,
+      "Should only get 3 frames.");
+    is(gDebugger.document.querySelectorAll(".dbg-stackframe-black-boxed").length, 1,
+      "And one of them should be the combined black boxed frames.");
   });
 
-  gDebuggee.runTest();
+  // Spin the event loop before causing the debuggee to pause, to allow
+  // this function to return first.
+  executeSoon(() => gDebuggee.runTest());
+  return finished;
 }
 
-function getBlackBoxCheckbox(url) {
+function getBlackBoxCheckbox(aUrl) {
   return gDebugger.document.querySelector(
-    ".side-menu-widget-item[tooltiptext=\""
-      + url + "\"] .side-menu-widget-item-checkbox");
-}
-
-function once(target, event, callback) {
-  target.addEventListener(event, function _listener(...args) {
-    target.removeEventListener(event, _listener, false);
-    callback.apply(null, args);
-  }, false);
+    ".side-menu-widget-item[tooltiptext=\"" + aUrl + "\"] " +
+    ".side-menu-widget-item-checkbox");
 }
 
 registerCleanupFunction(function() {
-  removeTab(gTab);
-  gPane = null;
   gTab = null;
   gDebuggee = null;
+  gPanel = null;
   gDebugger = null;
+  gFrames = null;
 });
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-03.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-03.js
index bc6a22e5e0cd..5ab8675fb1be 100644
--- a/browser/devtools/debugger/test/browser_dbg_blackboxing-03.js
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-03.js
@@ -6,88 +6,63 @@
  * view when we are already paused.
  */
 
-const TAB_URL = EXAMPLE_URL + "browser_dbg_blackboxing.html";
-const BLACKBOXME_URL = EXAMPLE_URL + "blackboxing_blackboxme.js"
+const TAB_URL = EXAMPLE_URL + "doc_blackboxing.html";
+const BLACKBOXME_URL = EXAMPLE_URL + "code_blackboxing_blackboxme.js"
 
-var gPane = null;
-var gTab = null;
-var gDebuggee = null;
-var gDebugger = null;
+let gTab, gDebuggee, gPanel, gDebugger;
+let gFrames;
 
-function test()
-{
-  let scriptShown = false;
-  let framesAdded = false;
-  let resumed = false;
-  let testStarted = false;
-
-  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
-    resumed = true;
+function test() {
+  initDebugger(TAB_URL).then(([aTab, aDebuggee, aPanel]) => {
     gTab = aTab;
     gDebuggee = aDebuggee;
-    gPane = aPane;
-    gDebugger = gPane.panelWin;
+    gPanel = aPanel;
+    gDebugger = gPanel.panelWin;
+    gFrames = gDebugger.DebuggerView.StackFrames;
 
-    once(gDebugger, "Debugger:SourceShown", function () {
-      testBlackBoxStack();
-    });
+    waitForSourceAndCaretAndScopes(gPanel, ".html", 21)
+      .then(testBlackBoxStack)
+      .then(testBlackBoxSource)
+      .then(() => resumeDebuggerThenCloseAndFinish(gPanel))
+      .then(null, aError => {
+        ok(false, "Got an error: " + aError.message + "\n" + aError.stack);
+      });
+
+    gDebuggee.runTest();
   });
 }
 
 function testBlackBoxStack() {
-  const { activeThread } = gDebugger.DebuggerController;
-  activeThread.addOneTimeListener("framesadded", function () {
-    const frames = gDebugger.DebuggerView.StackFrames.widget._list;
-
-    is(frames.querySelectorAll(".dbg-stackframe").length, 6,
-       "Should get 6 frames");
-
-    is(frames.querySelectorAll(".dbg-stackframe-black-boxed").length, 0,
-       "And none of them are black boxed");
-
-    testBlackBoxSource();
-  });
-
-  gDebuggee.runTest();
+  is(gFrames.itemCount, 6,
+    "Should get 6 frames.");
+  is(gDebugger.document.querySelectorAll(".dbg-stackframe-black-boxed").length, 0,
+    "And none of them are black boxed.");
 }
 
 function testBlackBoxSource() {
-  const checkbox = getBlackBoxCheckbox(BLACKBOXME_URL);
-  ok(checkbox, "Should get the checkbox for black boxing the source");
+  let finished = waitForThreadEvents(gPanel, "blackboxchange").then(aSource => {
+    ok(aSource.isBlackBoxed, "The source should be black boxed now.");
 
-  const { activeThread } = gDebugger.DebuggerController;
-  activeThread.addOneTimeListener("blackboxchange", function (event, sourceClient) {
-    ok(sourceClient.isBlackBoxed, "The source should be black boxed now");
-
-    const frames = gDebugger.DebuggerView.StackFrames.widget._list;
-    is(frames.querySelectorAll(".dbg-stackframe").length, 3,
-       "Should only get 3 frames");
-    is(frames.querySelectorAll(".dbg-stackframe-black-boxed").length, 1,
-       "And one of them is the combined black boxed frames");
-
-    closeDebuggerAndFinish();
+    is(gFrames.itemCount, 3,
+      "Should only get 3 frames.");
+    is(gDebugger.document.querySelectorAll(".dbg-stackframe-black-boxed").length, 1,
+      "And one of them should be the combined black boxed frames.");
   });
 
-  checkbox.click();
+  getBlackBoxCheckbox(BLACKBOXME_URL).click();
+  return finished;
 }
 
-function getBlackBoxCheckbox(url) {
+function getBlackBoxCheckbox(aUrl) {
   return gDebugger.document.querySelector(
-    ".side-menu-widget-item[tooltiptext=\""
-      + url + "\"] .side-menu-widget-item-checkbox");
-}
-
-function once(target, event, callback) {
-  target.addEventListener(event, function _listener(...args) {
-    target.removeEventListener(event, _listener, false);
-    callback.apply(null, args);
-  }, false);
+    ".side-menu-widget-item[tooltiptext=\"" + aUrl + "\"] " +
+    ".side-menu-widget-item-checkbox");
 }
 
 registerCleanupFunction(function() {
-  removeTab(gTab);
-  gPane = null;
   gTab = null;
   gDebuggee = null;
+  gPanel = null;
   gDebugger = null;
+  gFrames = null;
 });
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-04.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-04.js
index 30286a2f71b2..72a3d05e42ca 100644
--- a/browser/devtools/debugger/test/browser_dbg_blackboxing-04.js
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-04.js
@@ -6,78 +6,62 @@
  * for all of them.
  */
 
-const TAB_URL = EXAMPLE_URL + "browser_dbg_blackboxing.html";
+const TAB_URL = EXAMPLE_URL + "doc_blackboxing.html";
+const BLACKBOXME_URL = EXAMPLE_URL + "code_blackboxing_blackboxme.js"
 
-var gPane = null;
-var gTab = null;
-var gDebuggee = null;
-var gDebugger = null;
+let gTab, gDebuggee, gPanel, gDebugger;
+let gFrames;
 
-function test()
-{
-  let scriptShown = false;
-  let framesAdded = false;
-  let resumed = false;
-  let testStarted = false;
-
-  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
-    resumed = true;
+function test() {
+  initDebugger(TAB_URL).then(([aTab, aDebuggee, aPanel]) => {
     gTab = aTab;
     gDebuggee = aDebuggee;
-    gPane = aPane;
-    gDebugger = gPane.panelWin;
+    gPanel = aPanel;
+    gDebugger = gPanel.panelWin;
+    gFrames = gDebugger.DebuggerView.StackFrames;
 
-    once(gDebugger, "Debugger:SourceShown", function () {
-      blackBoxSources();
-    });
+    waitForSourceShown(gPanel, BLACKBOXME_URL)
+      .then(blackBoxSources)
+      .then(testBlackBoxStack)
+      .then(() => resumeDebuggerThenCloseAndFinish(gPanel))
+      .then(null, aError => {
+        ok(false, "Got an error: " + aError.message + "\n" + aError.stack);
+      });
   });
 }
 
 function blackBoxSources() {
-  let timesFired = 0;
-  const { activeThread } = gDebugger.DebuggerController;
-  activeThread.addListener("blackboxchange", function _onBlackBoxChange() {
-    if (++timesFired !== 3) {
-      return;
-    }
-    activeThread.removeListener("blackboxchange", _onBlackBoxChange);
-
-    activeThread.addOneTimeListener("framesadded", testStackFrames);
-    gDebuggee.one();
-  }, false);
-
-  getBlackBoxCheckbox(EXAMPLE_URL + "blackboxing_one.js").click();
-  getBlackBoxCheckbox(EXAMPLE_URL + "blackboxing_two.js").click();
-  getBlackBoxCheckbox(EXAMPLE_URL + "blackboxing_three.js").click();
+  let finished = waitForThreadEvents(gPanel, "blackboxchange", 3);
+  getBlackBoxCheckbox(EXAMPLE_URL + "code_blackboxing_one.js").click();
+  getBlackBoxCheckbox(EXAMPLE_URL + "code_blackboxing_two.js").click();
+  getBlackBoxCheckbox(EXAMPLE_URL + "code_blackboxing_three.js").click();
+  return finished;
 }
 
-function testStackFrames() {
-  const frames = gDebugger.DebuggerView.StackFrames.widget._list;
-  is(frames.querySelectorAll(".dbg-stackframe").length, 4,
-     "Should get 4 frames (one -> two -> three -> doDebuggerStatement)");
-  is(frames.querySelectorAll(".dbg-stackframe-black-boxed").length, 3,
-     "And one, two, and three should each have their own black boxed frame.");
+function testBlackBoxStack() {
+  let finished = waitForSourceAndCaretAndScopes(gPanel, ".html", 21).then(() => {
+    is(gFrames.itemCount, 4,
+      "Should get 4 frames (one -> two -> three -> doDebuggerStatement).");
+    is(gDebugger.document.querySelectorAll(".dbg-stackframe-black-boxed").length, 3,
+      "And 'one', 'two', and 'three' should each have their own black boxed frame.");
+  });
 
-  closeDebuggerAndFinish();
+  // Spin the event loop before causing the debuggee to pause, to allow
+  // this function to return first.
+  executeSoon(() => gDebuggee.one());
+  return finished;
 }
 
-function getBlackBoxCheckbox(url) {
+function getBlackBoxCheckbox(aUrl) {
   return gDebugger.document.querySelector(
-    ".side-menu-widget-item[tooltiptext=\""
-      + url + "\"] .side-menu-widget-item-checkbox");
-}
-
-function once(target, event, callback) {
-  target.addEventListener(event, function _listener(...args) {
-    target.removeEventListener(event, _listener, false);
-    callback.apply(null, args);
-  }, false);
+    ".side-menu-widget-item[tooltiptext=\"" + aUrl + "\"] " +
+    ".side-menu-widget-item-checkbox");
 }
 
 registerCleanupFunction(function() {
-  removeTab(gTab);
-  gPane = null;
   gTab = null;
   gDebuggee = null;
+  gPanel = null;
   gDebugger = null;
+  gFrames = null;
 });
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-05.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-05.js
index fea5a014bfb6..879e278c35b8 100644
--- a/browser/devtools/debugger/test/browser_dbg_blackboxing-05.js
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-05.js
@@ -2,67 +2,61 @@
    http://creativecommons.org/publicdomain/zero/1.0/ */
 
 /**
- * Test that we get a stack frame for each black boxed source, not a single one
- * for all of them.
+ * Test that a "this source is blackboxed" message is shown when necessary
+ * and can be properly dismissed.
  */
 
-const TAB_URL = EXAMPLE_URL + "binary_search.html";
+const TAB_URL = EXAMPLE_URL + "doc_binary_search.html";
 
-var gPane = null;
-var gTab = null;
-var gDebuggee = null;
-var gDebugger = null;
+let gTab, gDebuggee, gPanel, gDebugger;
+let gDeck;
 
-function test()
-{
-  let scriptShown = false;
-  let framesAdded = false;
-  let resumed = false;
-  let testStarted = false;
-
-  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
-    resumed = true;
+function test() {
+  initDebugger(TAB_URL).then(([aTab, aDebuggee, aPanel]) => {
     gTab = aTab;
     gDebuggee = aDebuggee;
-    gPane = aPane;
-    gDebugger = gPane.panelWin;
+    gPanel = aPanel;
+    gDebugger = gPanel.panelWin;
+    gDeck = gDebugger.document.getElementById("editor-deck");
 
-    once(gDebugger, "Debugger:SourceShown", testSourceEditorShown);
+    waitForSourceShown(gPanel, ".coffee")
+      .then(testSourceEditorShown)
+      .then(blackBoxSource)
+      .then(testBlackBoxMessageShown)
+      .then(clickStopBlackBoxingButton)
+      .then(testSourceEditorShownAgain)
+      .then(() => closeDebuggerAndFinish(gPanel))
+      .then(null, aError => {
+        ok(false, "Got an error: " + aError.message + "\n" + aError.stack);
+      });
   });
 }
 
 function testSourceEditorShown() {
-  const deck = gDebugger.document.getElementById("editor-deck");
-  is(deck.selectedIndex, "0",
-     "The first item in the deck should be selected (the source editor)");
-  blackBoxSource();
+  is(gDeck.selectedIndex, "0",
+    "The first item in the deck should be selected (the source editor).");
 }
 
 function blackBoxSource() {
-  const { activeThread } = gDebugger.DebuggerController;
-  activeThread.addOneTimeListener("blackboxchange", testBlackBoxMessageShown);
+  let finished = waitForThreadEvents(gPanel, "blackboxchange");
   getAnyBlackBoxCheckbox().click();
+  return finished;
 }
 
 function testBlackBoxMessageShown() {
-  const deck = gDebugger.document.getElementById("editor-deck");
-  is(deck.selectedIndex, "1",
-     "The second item in the deck should be selected (the black box message)");
-  clickStopBlackBoxingButton();
+  is(gDeck.selectedIndex, "1",
+    "The second item in the deck should be selected (the black box message).");
 }
 
 function clickStopBlackBoxingButton() {
-  const button = gDebugger.document.getElementById("black-boxed-message-button");
-  const { activeThread } = gDebugger.DebuggerController;
-  activeThread.addOneTimeListener("blackboxchange", testSourceEditorShownAgain);
-  button.click();
+  let finished = waitForThreadEvents(gPanel, "blackboxchange");
+  getEditorBlackboxMessageButton().click();
+  return finished;
 }
 
 function testSourceEditorShownAgain() {
-  const deck = gDebugger.document.getElementById("editor-deck");
-  is(deck.selectedIndex, "0",
-     "The first item in the deck should be selected again (the source editor)");
-  closeDebuggerAndFinish();
+  is(gDeck.selectedIndex, "0",
+    "The first item in the deck should be selected again (the source editor).");
 }
 
 function getAnyBlackBoxCheckbox() {
@@ -70,17 +64,14 @@ function getAnyBlackBoxCheckbox() {
     ".side-menu-widget-item .side-menu-widget-item-checkbox");
 }
 
-function once(target, event, callback) {
-  target.addEventListener(event, function _listener(...args) {
-    target.removeEventListener(event, _listener, false);
-    callback.apply(null, args);
-  }, false);
+function getEditorBlackboxMessageButton() {
+  return gDebugger.document.getElementById("black-boxed-message-button");
 }
 
 registerCleanupFunction(function() {
-  removeTab(gTab);
-  gPane = null;
   gTab = null;
   gDebuggee = null;
+  gPanel = null;
   gDebugger = null;
+  gDeck = null;
 });
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-06.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-06.js
index 1b2aa607f400..4637f26bbc91 100644
--- a/browser/devtools/debugger/test/browser_dbg_blackboxing-06.js
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-06.js
@@ -5,66 +5,52 @@
  * Test that clicking the black box checkbox doesn't select that source.
  */
 
-const TAB_URL = EXAMPLE_URL + "browser_dbg_blackboxing.html";
+const TAB_URL = EXAMPLE_URL + "doc_blackboxing.html";
 
-var gPane = null;
-var gTab = null;
-var gDebuggee = null;
-var gDebugger = null;
+let gTab, gDebuggee, gPanel, gDebugger;
+let gSources;
 
-function test()
-{
-  let scriptShown = false;
-  let framesAdded = false;
-  let resumed = false;
-  let testStarted = false;
-
-  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
-    resumed = true;
+function test() {
+  initDebugger(TAB_URL).then(([aTab, aDebuggee, aPanel]) => {
     gTab = aTab;
     gDebuggee = aDebuggee;
-    gPane = aPane;
-    gDebugger = gPane.panelWin;
+    gPanel = aPanel;
+    gDebugger = gPanel.panelWin;
+    gSources = gDebugger.DebuggerView.Sources;
 
-    once(gDebugger, "Debugger:SourceShown", testBlackBox);
+    waitForSourceShown(gPanel, ".js")
+      .then(testBlackBox)
+      .then(() => closeDebuggerAndFinish(gPanel))
+      .then(null, aError => {
+        ok(false, "Got an error: " + aError.message + "\n" + aError.stack);
+      });
   });
 }
 
 function testBlackBox() {
-  const sources = gDebugger.DebuggerView.Sources;
-
-  const selectedUrl = sources.selectedItem.attachment.source.url;
+  const selectedUrl = gSources.selectedValue;
   const checkbox = getDifferentBlackBoxCheckbox(selectedUrl);
-  ok(checkbox, "We should be able to grab a checkbox");
+  ok(checkbox, "We should be able to grab a different checkbox.");
 
-  const { activeThread } = gDebugger.DebuggerController;
-  activeThread.addOneTimeListener("blackboxchange", function () {
-    is(selectedUrl,
-       sources.selectedItem.attachment.source.url,
-       "The same source should be selected");
-    closeDebuggerAndFinish();
+  let finished = waitForThreadEvents(gPanel, "blackboxchange").then(() => {
+    is(selectedUrl, gSources.selectedValue,
+      "The same source should still be selected.");
   });
 
   checkbox.click();
+  return finished;
 }
 
-function getDifferentBlackBoxCheckbox(url) {
+function getDifferentBlackBoxCheckbox(aUrl) {
   return gDebugger.document.querySelector(
-    ".side-menu-widget-item:not([tooltiptext=\""
-      + url + "\"]) .side-menu-widget-item-checkbox");
-}
-
-function once(target, event, callback) {
-  target.addEventListener(event, function _listener(...args) {
-    target.removeEventListener(event, _listener, false);
-    callback.apply(null, args);
-  }, false);
+    ".side-menu-widget-item:not([tooltiptext=\"" + aUrl + "\"]) " +
+    ".side-menu-widget-item-checkbox");
 }
 
 registerCleanupFunction(function() {
-  removeTab(gTab);
-  gPane = null;
   gTab = null;
   gDebuggee = null;
+  gPanel = null;
   gDebugger = null;
+  gSources = null;
 });
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-07.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-07.js
index ed2bbd009111..dacc04c889dc 100644
--- a/browser/devtools/debugger/test/browser_dbg_blackboxing-07.js
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-07.js
@@ -6,81 +6,61 @@
  * currently paused frame's source.
  */
 
-const TAB_URL = EXAMPLE_URL + "browser_dbg_blackboxing.html";
+const TAB_URL = EXAMPLE_URL + "doc_blackboxing.html";
 
-var gPane = null;
-var gTab = null;
-var gDebuggee = null;
-var gDebugger = null;
+let gTab, gDebuggee, gPanel, gDebugger;
+let gSources;
 
-function test()
-{
-  let scriptShown = false;
-  let framesAdded = false;
-  let resumed = false;
-  let testStarted = false;
-
-  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
-    resumed = true;
+function test() {
+  initDebugger(TAB_URL).then(([aTab, aDebuggee, aPanel]) => {
     gTab = aTab;
     gDebuggee = aDebuggee;
-    gPane = aPane;
-    gDebugger = gPane.panelWin;
+    gPanel = aPanel;
+    gDebugger = gPanel.panelWin;
+    gSources = gDebugger.DebuggerView.Sources;
 
-    once(gDebugger, "Debugger:SourceShown", runTest);
-  });
-}
-
-function runTest() {
-  const { activeThread } = gDebugger.DebuggerController;
-  activeThread.addOneTimeListener("paused", function () {
-    const sources = gDebugger.DebuggerView.Sources;
-    const selectedUrl = sources.selectedItem.attachment.source.url;
-
-    once(gDebugger, "Debugger:SourceShown", function () {
-      const newSelectedUrl = sources.selectedItem.attachment.source.url;
-      isnot(selectedUrl, newSelectedUrl,
-            "Should not have the same url selected");
-
-      activeThread.addOneTimeListener("blackboxchange", function () {
-        isnot(sources.selectedItem.attachment.source.url,
-              selectedUrl,
-              "The selected source did not change");
-        closeDebuggerAndFinish();
+    waitForSourceAndCaretAndScopes(gPanel, ".html", 21)
+      .then(testBlackBox)
+      .then(() => resumeDebuggerThenCloseAndFinish(gPanel))
+      .then(null, aError => {
+        ok(false, "Got an error: " + aError.message + "\n" + aError.stack);
       });
 
-      getBlackBoxCheckbox(newSelectedUrl).click();
+    gDebuggee.runTest();
+  });
+}
+
+function testBlackBox() {
+  const selectedUrl = gSources.selectedValue;
+
+  let finished = waitForSourceShown(gPanel, "blackboxme.js").then(() => {
+    const newSelectedUrl = gSources.selectedValue;
+    isnot(selectedUrl, newSelectedUrl,
+      "Should not have the same url selected.");
+
+    let finished = waitForThreadEvents(gPanel, "blackboxchange").then(() => {
+      is(gSources.selectedValue, newSelectedUrl,
+        "The selected source did not change.");
     });
 
-    getDifferentSource(selectedUrl).click();
+    getBlackBoxCheckbox(newSelectedUrl).click()
+    return finished;
   });
 
-  gDebuggee.runTest();
+  gSources.selectedIndex = 0;
+  return finished;
 }
 
-function getDifferentSource(url) {
+function getBlackBoxCheckbox(aUrl) {
   return gDebugger.document.querySelector(
-    ".side-menu-widget-item:not([tooltiptext=\""
-      + url + "\"])");
-}
-
-function getBlackBoxCheckbox(url) {
-  return gDebugger.document.querySelector(
-    ".side-menu-widget-item[tooltiptext=\""
-      + url + "\"] .side-menu-widget-item-checkbox");
-}
-
-function once(target, event, callback) {
-  target.addEventListener(event, function _listener(...args) {
-    target.removeEventListener(event, _listener, false);
-    callback.apply(null, args);
-  }, false);
+    ".side-menu-widget-item[tooltiptext=\"" + aUrl + "\"] " +
+    ".side-menu-widget-item-checkbox");
 }
 
 registerCleanupFunction(function() {
-  removeTab(gTab);
-  gPane = null;
   gTab = null;
   gDebuggee = null;
+  gPanel = null;
   gDebugger = null;
+  gSources = null;
 });