Bug 1391239 - Make AltGr-Enter in the search bar open a new tab. r=adw

***
Fix Bug 1391239.

Differential Revision: https://phabricator.services.mozilla.com/D51504

--HG--
extra : moz-landing-system : lando

browser/components/search/content/searchbar.js

@@ -303,7 +303,9 @@
       } else {
         let newTabPref = Services.prefs.getBoolPref("browser.search.openintab");
         if (
-          (aEvent instanceof KeyboardEvent && aEvent.altKey) ^ newTabPref &&
+          (aEvent instanceof KeyboardEvent &&
+            (aEvent.altKey || aEvent.getModifierState("AltGraph"))) ^
+            newTabPref &&
           !gBrowser.selectedTab.isEmpty
         ) {
           where = "tab";

browser/components/search/test/browser/browser_426329.js

@@ -195,6 +195,20 @@ add_task(async function testAltReturn() {
   );
 });
 
+add_task(async function testAltGrReturn() {
+  await prepareTest();
+  await BrowserTestUtils.openNewForegroundTab(gBrowser, () => {
+    EventUtils.synthesizeKey("KEY_Enter", { altGraphKey: true });
+  });
+
+  is(gBrowser.tabs.length, preTabNo + 1, "AltGr+Return key added new tab");
+  is(
+    gBrowser.currentURI.spec,
+    expectedURL(searchBar.value),
+    "testAltGrReturn opened correct search page"
+  );
+});
+
 // Shift key has no effect for now, so skip it
 add_task(async function testShiftAltReturn() {
   /*