Bug 1744243 follow-up - Fix test_URIFixup_external_protocol_fallback.…

…js when run in Thunderbird. r=daisuke

Differential Revision: https://phabricator.services.mozilla.com/D154475

docshell/test/unit/test_URIFixup_external_protocol_fallback.js

@@ -6,6 +6,9 @@
 
 // Test whether fallback mechanism is working if don't trust nsIExternalProtocolService.
 
+const { AppConstants } = ChromeUtils.import(
+  "resource://gre/modules/AppConstants.jsm"
+);
 const { MockRegistrar } = ChromeUtils.import(
   "resource://testing-common/MockRegistrar.jsm"
 );
@@ -60,9 +63,12 @@ add_task(function basic() {
   const testData = [
     {
       input: "mailto:[email protected]",
-      expected: isSupportedInHandlerService("mailto")
-        ? "mailto:[email protected]"
-        : "http://mailto:[email protected]/",
+      expected:
+        isSupportedInHandlerService("mailto") ||
+        // Thunderbird IS a mailto handler, it doesn't have handlers.
+        AppConstants.MOZ_APP_NAME == "thunderbird"
+          ? "mailto:[email protected]"
+          : "http://mailto:[email protected]/",
     },
     {
       input: "keyword:search",