diff --git a/devtools/client/preferences/devtools-client.js b/devtools/client/preferences/devtools-client.js
index eaddd09bd90d..c38afeed4739 100644
--- a/devtools/client/preferences/devtools-client.js
+++ b/devtools/client/preferences/devtools-client.js
@@ -266,10 +266,6 @@ pref("devtools.netmonitor.persistlog", false);
 // any timestamps.
 pref("devtools.webconsole.timestampMessages", false);
 
-// Web Console automatic multiline mode: |true| if you want incomplete statements
-// to automatically trigger multiline editing (equivalent to shift + enter).
-pref("devtools.webconsole.autoMultiline", true);
-
 // Enable the webconsole sidebar toggle in Nightly builds.
 #if defined(NIGHTLY_BUILD)
 pref("devtools.webconsole.sidebarToggle", true);
diff --git a/devtools/client/webconsole/components/JSTerm.js b/devtools/client/webconsole/components/JSTerm.js
index 66199a98a81c..77d29d49ff11 100644
--- a/devtools/client/webconsole/components/JSTerm.js
+++ b/devtools/client/webconsole/components/JSTerm.js
@@ -23,7 +23,6 @@ loader.lazyRequireGetter(this, "Telemetry", "devtools/client/shared/telemetry");
 const l10n = require("devtools/client/webconsole/webconsole-l10n");
 
 const HELP_URL = "https://developer.mozilla.org/docs/Tools/Web_Console/Helpers";
-const PREF_AUTO_MULTILINE = "devtools.webconsole.autoMultiline";
 
 function gSequenceId() {
   return gSequenceId.n++;
@@ -201,16 +200,13 @@ class JSTerm extends Component {
           viewportMargin: Infinity,
           extraKeys: {
             "Enter": (e, cm) => {
-              let autoMultiline = Services.prefs.getBoolPref(PREF_AUTO_MULTILINE);
-              if (e.shiftKey
-                || (
-                  !Debugger.isCompilableUnit(this.getInputValue())
-                  && autoMultiline
-                )
-              ) {
+              if (!this.autocompletePopup.isOpen && (
+                e.shiftKey || !Debugger.isCompilableUnit(this.getInputValue())
+              )) {
                 // shift return or incomplete statement
                 return "CodeMirror.Pass";
               }
+
               this.execute();
               return null;
             },
@@ -685,9 +681,9 @@ class JSTerm extends Component {
       }
       return;
     } else if (event.keyCode == KeyCodes.DOM_VK_RETURN) {
-      let autoMultiline = Services.prefs.getBoolPref(PREF_AUTO_MULTILINE);
-      if (event.shiftKey ||
-          (!Debugger.isCompilableUnit(inputNode.value) && autoMultiline)) {
+      if (!this.autocompletePopup.isOpen && (
+        event.shiftKey || !Debugger.isCompilableUnit(this.getInputValue())
+      )) {
         // shift return or incomplete statement
         return;
       }
diff --git a/devtools/client/webconsole/local-dev/index.js b/devtools/client/webconsole/local-dev/index.js
index 3215e1b2f8e1..628e548d2292 100644
--- a/devtools/client/webconsole/local-dev/index.js
+++ b/devtools/client/webconsole/local-dev/index.js
@@ -37,7 +37,6 @@ pref("devtools.webconsole.ui.filterbar", false);
 pref("devtools.webconsole.inputHistoryCount", 50);
 pref("devtools.webconsole.persistlog", false);
 pref("devtools.webconsole.timestampMessages", false);
-pref("devtools.webconsole.autoMultiline", true);
 pref("devtools.webconsole.sidebarToggle", true);
 
 const WebConsoleOutputWrapper = require("../webconsole-output-wrapper");
diff --git a/devtools/client/webconsole/test/mocha-test-setup.js b/devtools/client/webconsole/test/mocha-test-setup.js
index ac4a44649092..b83335e7a2ae 100644
--- a/devtools/client/webconsole/test/mocha-test-setup.js
+++ b/devtools/client/webconsole/test/mocha-test-setup.js
@@ -23,7 +23,6 @@ pref("devtools.webconsole.ui.filterbar", false);
 pref("devtools.webconsole.inputHistoryCount", 50);
 pref("devtools.webconsole.persistlog", false);
 pref("devtools.webconsole.timestampMessages", false);
-pref("devtools.webconsole.autoMultiline", true);
 pref("devtools.webconsole.sidebarToggle", true);
 
 global.loader = {
diff --git a/devtools/client/webconsole/test/mochitest/browser_jsterm_autocomplete_return_key.js b/devtools/client/webconsole/test/mochitest/browser_jsterm_autocomplete_return_key.js
index b86c3034ad83..17f563ecf560 100644
--- a/devtools/client/webconsole/test/mochitest/browser_jsterm_autocomplete_return_key.js
+++ b/devtools/client/webconsole/test/mochitest/browser_jsterm_autocomplete_return_key.js
@@ -24,12 +24,7 @@ const TEST_URI = `data:text/html;charset=utf-8,
 </head>
 <body>bug 585991 - test pressing return with open popup</body>`;
 
-// We should turn off auto-multiline editing during these tests
-const PREF_AUTO_MULTILINE = "devtools.webconsole.autoMultiline";
-
 add_task(async function() {
-  Services.prefs.setBoolPref(PREF_AUTO_MULTILINE, false);
-
   let { jsterm } = await openNewTabAndConsole(TEST_URI);
   const {
     autocompletePopup: popup,
@@ -74,6 +69,4 @@ add_task(async function() {
   is(jsterm.getInputValue(), "window.foobar.item3",
     "completion was successful after KEY_Enter");
   ok(!completeNode.value, "completeNode is empty");
-
-  Services.prefs.clearUserPref(PREF_AUTO_MULTILINE);
 });