Show accessKey when press alt

chrome/content/zotero/menuAccessKey.js

@@ -0,0 +1,113 @@
+/*
+    ***** BEGIN LICENSE BLOCK *****
+    
+    Copyright © 2009-2023 Center for History and New Media
+                          George Mason University, Fairfax, Virginia, USA
+                          http://zotero.org
+    
+    This file is part of Zotero.
+    
+    Zotero is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+    
+    Zotero is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+    
+    You should have received a copy of the GNU Affero General Public License
+    along with Zotero.  If not, see <http://www.gnu.org/licenses/>.
+    
+    ***** END LICENSE BLOCK *****
+*/
+
+(() => {
+if (Zotero.isMac) {
+	return;
+}
+
+const WAIT_ALT_KEY = 100;
+
+let menuBar;
+let isMenuActive = false;
+let accessKeysHidden = false;
+let altPressTime = 0;
+
+if (document.readyState === "complete") {
+	init();
+}
+else {
+	document.addEventListener('DOMContentLoaded', init);
+}
+
+function init() {
+	setAccessKeysHidden(true);
+
+	menuBar = document.querySelector("#main-menubar");
+
+	// Submenu accessKey is not loaded until popupshowing event
+	menuBar.addEventListener("popupshowing", () => {
+		if (accessKeysHidden) {
+			setAccessKeysHidden(true);
+		}
+	});
+
+	window.addEventListener("keyup", (e) => {
+		if (e.key === "Alt") {
+			altPressTime = new Date().getTime();
+		}
+	});
+
+	observeMenuActive(menuBar);
+}
+
+async function setAccessKeysHidden(hidden = false) {
+	accessKeysHidden = hidden;
+	if (!hidden) {
+		document.querySelectorAll('label[cachedAccessKey]').forEach((label) => {
+			label.accessKey = label.getAttribute("cachedAccessKey");
+		});
+		return;
+	}
+	document.querySelectorAll('*[accesskey]').forEach((e) => {
+		const label = e.querySelector("label");
+		if (!label?.accessKey) {
+			return;
+		}
+		label.setAttribute('cachedAccessKey', label.accessKey);
+		label.accessKey = "";
+	});
+}
+
+function observeMenuActive() {
+	let observer = new MutationObserver(async () => {
+		if (menuBar.querySelector(":scope > menu[_moz-menuactive]")) {
+			isMenuActive = true;
+			// When alt key is pressed, show access key
+			if (accessKeysHidden && (new Date().getTime() - altPressTime < WAIT_ALT_KEY)) {
+				setAccessKeysHidden(false);
+			}
+		}
+		else {
+			isMenuActive = false;
+			tryHideAccessKeys();
+		}
+	});
+	menuBar.querySelectorAll(":scope > menu").forEach((menu) => {
+		observer.observe(menu, { attributes: true, attributeFilter: ["_moz-menuactive"] });
+	});
+	window.addEventListener("unload", () => {
+		observer.disconnect();
+	});
+}
+
+async function tryHideAccessKeys() {
+	await Zotero.Promise.delay(WAIT_ALT_KEY);
+	if (isMenuActive || accessKeysHidden) {
+		return;
+	}
+	setAccessKeysHidden(true);
+}
+})();

chrome/content/zotero/zoteroPane.xhtml

@@ -89,6 +89,7 @@
 		Services.scriptloader.loadSubScript("chrome://zotero/content/progressQueueDialog.js", this);
 		Services.scriptloader.loadSubScript("chrome://zotero/content/lookup.js", this);
 		Services.scriptloader.loadSubScript("chrome://zotero/content/locateMenu.js", this);
+		Services.scriptloader.loadSubScript("chrome://zotero/content/menuAccessKey.js", this);
 		Services.scriptloader.loadSubScript("chrome://zotero/content/tooltip.js", this);
 		Services.scriptloader.loadSubScript("chrome://zotero/content/containers/tagSelectorContainer.js", this);
 	</script>