Bug 1901826 - prevent tab preview from triggering fullscreen toolbar autohide. r=dao,jswinarton

Differential Revision: https://phabricator.services.mozilla.com/D218432

browser/base/content/browser-fullScreenAndPointerLock.js

@@ -798,7 +798,7 @@ var FullScreen = {
     // e.g. we wouldn't want the autoscroll icon firing this event, so when the user
     // toggles chrome when moving mouse to the top, it doesn't go away again.
     let target = aEvent.originalTarget;
-    if (target.localName == "tooltip") {
+    if (target.localName == "tooltip" || target.id == "tab-preview-panel") {
       return;
     }
     if (

browser/base/content/test/fullscreen/browser.toml

@@ -49,6 +49,8 @@ skip-if = [
 
 ["browser_fullscreen_newwindow.js"]
 
+["browser_fullscreen_tab_preview.js"]
+
 ["browser_fullscreen_permissions_prompt.js"]
 
 ["browser_fullscreen_warning.js"]

browser/base/content/test/fullscreen/browser_fullscreen_tab_preview.js

@@ -0,0 +1,80 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// This test ensures dismissing a tab preview does not hide the nav toolbox
+// when browser.fullscreen.autohide is true.
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["browser.fullscreen.autohide", true],
+      ["browser.tabs.hoverPreview.enabled", true],
+      ["ui.tooltip.delay_ms", 0],
+    ],
+  });
+});
+
+add_task(async function testTabPreview() {
+  let tab = BrowserTestUtils.addTab(gBrowser, "about:blank");
+  let onFullscreen = Promise.all([
+    BrowserTestUtils.waitForEvent(window, "fullscreen"),
+    BrowserTestUtils.waitForEvent(
+      window,
+      "sizemodechange",
+      false,
+      () => window.fullScreen
+    ),
+  ]);
+  document.getElementById("View:FullScreen").doCommand();
+  await onFullscreen;
+  // make sure the toolbox is visible if it's autohidden
+  FullScreen.showNavToolbox();
+
+  let tabPreviewPanel = document.getElementById("tab-preview-panel");
+  // open tab preview
+  const previewShown = BrowserTestUtils.waitForPopupEvent(
+    tabPreviewPanel,
+    "shown"
+  );
+  EventUtils.synthesizeMouse(
+    tab,
+    1,
+    1,
+    {
+      type: "mouseover",
+    },
+    window
+  );
+  await previewShown;
+  // close tab preview
+  const previewHidden = BrowserTestUtils.waitForPopupEvent(
+    tabPreviewPanel,
+    "hidden"
+  );
+  EventUtils.synthesizeMouse(
+    document.getElementById("tabs-newtab-button"),
+    1,
+    1,
+    { type: "mouseover" }
+  );
+  await previewHidden;
+  // navtoolbox should still be visible
+  Assert.ok(
+    !FullScreen._isChromeCollapsed,
+    "Toolbar remains visible after tab preview is hidden"
+  );
+  BrowserTestUtils.removeTab(tab);
+  let onExitFullscreen = Promise.all([
+    BrowserTestUtils.waitForEvent(window, "fullscreen"),
+    BrowserTestUtils.waitForEvent(
+      window,
+      "sizemodechange",
+      false,
+      () => !window.fullScreen
+    ),
+  ]);
+  document.getElementById("View:FullScreen").doCommand();
+  await onExitFullscreen;
+});