--- a/testing/talos/talos/tests/devtools/addon/content/damp-tests.js
+++ b/testing/talos/talos/tests/devtools/addon/content/damp-tests.js
@@ -82,16 +82,20 @@ module.exports = [
     path: "debugger/custom.js"
   },
   // Run individual tests covering a very precise tool feature.
   {
     name: "console.bulklog",
     path: "webconsole/bulklog.js",
     description: "Measure time for a bunch of sync console.log statements to appear"
   }, {
+    name: "console.autocomplete",
+    path: "webconsole/autocomplete.js",
+    description: "Measure time for autocomplete popup to appear"
+  }, {
     name: "console.streamlog",
     path: "webconsole/streamlog.js",
     description: "Measure rAF on page during a stream of console.log statements"
   }, {
     name: "console.objectexpand",
     path: "webconsole/objectexpand.js",
     description: "Measure time to expand a large object and close the console"
   }, {

new file mode 100644
--- /dev/null
+++ b/testing/talos/talos/tests/devtools/addon/content/tests/webconsole/autocomplete.js
@@ -0,0 +1,74 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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/. */
+
+"use strict";
+
+const {
+  openToolbox,
+  closeToolbox,
+  runTest,
+  testSetup,
+  testTeardown,
+} = require("../head");
+
+const TEST_NAME = "console.autocomplete";
+
+module.exports = async function() {
+  await testSetup(`data:text/html,<meta charset=utf8><script>
+    /*
+     * Create an object with a null prototype in order to not have the autocomplete
+     * popup polluted by Object prototype methods.
+     */
+    const items = Object.create(null);
+    const itemsLength = 10000;
+    for (let i = 0; i < itemsLength; i++) {
+      const key = "item" + i;
+      items[key] = i;
+    }
+
+    window.autocompleteTest = items;
+  </script>`);
+
+  const toolbox = await openToolbox("webconsole");
+  const { hud } = toolbox.getPanel("webconsole");
+  const { jsterm } = hud;
+
+  const test = runTest(TEST_NAME);
+  const ITERATIONS = 5;
+  for (let i = 0; i < ITERATIONS; i++) {
+    await showAndHideAutoCompletePopup(jsterm);
+  }
+
+  test.done();
+
+  await closeToolbox();
+  await testTeardown();
+};
+
+async function showAndHideAutoCompletePopup(jsterm) {
+  await triggerAutocompletePopup(jsterm);
+  await hideAutocompletePopup(jsterm);
+}
+
+async function triggerAutocompletePopup(jsterm) {
+  jsterm.setInputValue("window.autocompleteTest.");
+  const onPopupOpened = jsterm.autocompletePopup.once("popup-opened");
+  // setInputValue does not trigger the autocompletion; we need to call `complete` in
+  // order to display the popup.
+  jsterm.complete(jsterm.COMPLETE_HINT_ONLY);
+  await onPopupOpened;
+
+  const onPopupUpdated = jsterm.once("autocomplete-updated");
+  jsterm.setInputValue("window.autocompleteTest.item9");
+  jsterm.complete(jsterm.COMPLETE_HINT_ONLY);
+
+  await onPopupUpdated;
+}
+
+function hideAutocompletePopup(jsterm) {
+  let onPopUpClosed = jsterm.autocompletePopup.once("popup-closed");
+  jsterm.setInputValue("");
+  jsterm.complete(jsterm.COMPLETE_HINT_ONLY);
+  return onPopUpClosed;
+}