diff --git a/browser/devtools/sourceeditor/autocomplete.js b/browser/devtools/sourceeditor/autocomplete.js
index 5cc0e69455f..3d032ba6d38 100644
--- a/browser/devtools/sourceeditor/autocomplete.js
+++ b/browser/devtools/sourceeditor/autocomplete.js
@@ -3,6 +3,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+const { Cu } = require("chrome");
 const cssAutoCompleter = require("devtools/sourceeditor/css-autocompleter");
 const { AutocompletePopup } = require("devtools/shared/autocomplete-popup");
 
@@ -215,7 +216,7 @@ function autoComplete({ ed, cm }) {
     private.suggestionInsertedOnce = false;
     // This event is used in tests.
     ed.emit("after-suggest");
-  });
+  }).then(null, Cu.reportError);
 }
 
 /**