1 files changed, 49 insertions, 0 deletions
diff --git a/devtools/client/aboutdebugging/test/browser/browser_aboutdebugging_addons_warnings.js b/devtools/client/aboutdebugging/test/browser/browser_aboutdebugging_addons_warnings.js
new file mode 100644
index 0000000000..db46754caa
--- /dev/null
+++ b/devtools/client/aboutdebugging/test/browser/browser_aboutdebugging_addons_warnings.js
@@ -0,0 +1,49 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/* import-globals-from helper-addons.js */
+Services.scriptloader.loadSubScript(CHROME_URL_ROOT + "helper-addons.js", this);
+
+// Test that extension warnings are displayed in about:debugging.
+add_task(async function () {
+  const EXTENSION_NAME = "Temporary web extension";
+  const EXTENSION_ID = "test-devtools@mozilla.org";
+
+  const { document, tab, window } = await openAboutDebugging();
+  await selectThisFirefoxPage(document, window.AboutDebugging.store);
+
+  await pushPref("extensions.webextensions.warnings-as-errors", false);
+  await installTemporaryExtensionFromXPI(
+    {
+      id: EXTENSION_ID,
+      name: EXTENSION_NAME,
+      extraProperties: {
+        // This property is not expected in the manifest and should trigger a warning!
+        wrongProperty: {},
+      },
+    },
+    document
+  );
+  await SpecialPowers.popPrefEnv();
+
+  info("Wait until a debug target item appears");
+  await waitUntil(() => findDebugTargetByText(EXTENSION_NAME, document));
+  const target = findDebugTargetByText(EXTENSION_NAME, document);
+
+  const warningMessage = target.querySelector(".qa-message");
+  ok(
+    !!warningMessage,
+    "A warning message is displayed for the installed addon"
+  );
+
+  const warningText = warningMessage.textContent;
+  ok(
+    warningText.includes("wrongProperty"),
+    "The warning message mentions wrongProperty"
+  );
+
+  await removeTemporaryExtension(EXTENSION_NAME, document);
+  await removeTab(tab);
+});