Hide context menu on mousedown, not click

app/create-bookmarks/contentscript.js

@@ -64,7 +64,7 @@ export default async function init(playlist) {
 		menuEl = html`
 			<ul class="context-menu" style="top: ${top}; left: ${left};">
 				<li>
-					<button onclick=${createBookmark}>
+					<button onclick=${() => { hideMenu(); createBookmark(); }}>
 						${browser.i18n.getMessage(end !== undefined
 							? 'bookmarkSelectionContextMenuItemForFragment'
 							: 'bookmarkSelectionContextMenuItemForSingleMoment'
@@ -76,7 +76,13 @@ export default async function init(playlist) {
 		document.body.appendChild(menuEl);
 	}
 
-	document.addEventListener('contextmenu', onContextMenu, false);
+	function onMouseDown(event) {
+		// A mouse-down outside the menu hides the menu.
+		if (menuEl && !menuEl.contains(event.target)) { // note nodeX.contains(nodeX) === true
+			hideMenu();
+		}
+	}
 
-	document.addEventListener('click', event => { hideMenu(); });
+	document.addEventListener('contextmenu', onContextMenu);
+	document.addEventListener('mousedown', onMouseDown);
 }