From 92dfac8c6445f19b2cb0343739fd0cfbd77cc663 Mon Sep 17 00:00:00 2001
From: Dan Stillman <dstillman@zotero.org>
Date: Fri, 4 Sep 2026 15:17:34 -0400
Subject: [PATCH] Don't make an unloaded tab reopenable with Undo Close Tab

unload() closes and re-adds the tab, and the close recorded an undo-close
history entry, so Undo Close Tab could open a duplicate of a tab that was
still open.
---
 chrome/content/zotero/tabs.js | 11 ++++++++---
 test/tests/tabsTest.js        | 18 ++++++++++++++++++
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/chrome/content/zotero/tabs.js b/chrome/content/zotero/tabs.js
index 8a1330b7c0..886441100c 100644
--- a/chrome/content/zotero/tabs.js
+++ b/chrome/content/zotero/tabs.js
@@ -722,8 +722,10 @@ var Zotero_Tabs = new function () {
 	 * Close tabs
 	 *
 	 * @param {String|Array<String>|undefined} ids One or more ids, or empty for the current tab
+	 * @param {Object} [options]
+	 * @param {Boolean} [options.skipHistory=false] - Don't make the tabs reopenable with undoClose()
 	 */
-	this.close = function (ids) {
+	this.close = function (ids, { skipHistory = false } = {}) {
 		if (!ids) {
 			ids = [this._selectedID];
 		}
@@ -779,7 +781,9 @@ var Zotero_Tabs = new function () {
 				}
 			});
 		}
-		this._history.push(historyEntry);
+		if (!skipHistory) {
+			this._history.push(historyEntry);
+		}
 		Zotero.Notifier.trigger('close', 'tab', [closedIDs], true);
 		this._update();
 	};
@@ -990,7 +994,8 @@ var Zotero_Tabs = new function () {
 			return;
 		}
 		var { tab, tabIndex } = this._getTab(id);
-		this.close(tab.id);
+		// The tab stays open, so it isn't reopenable
+		this.close(tab.id, { skipHistory: true });
 		this.add({
 			id: tab.id,
 			type: `${tab.type}-unloaded`,
diff --git a/test/tests/tabsTest.js b/test/tests/tabsTest.js
index 3d91882c0a..8e3a1a10b3 100644
--- a/test/tests/tabsTest.js
+++ b/test/tests/tabsTest.js
@@ -41,6 +41,24 @@ describe("Zotero_Tabs", function() {
 		});
 	});
 
+	describe("#unload()", function () {
+		it("should not make an unloaded tab reopenable", async function () {
+			let item = await createDataObject('item');
+			let attachment = await importPDFAttachment(item);
+			let reader = await Zotero.Reader.open(attachment.id);
+			let tabs = win.Zotero_Tabs;
+			tabs.select('zotero-pane');
+			let historyLength = tabs._history.length;
+			
+			tabs.unload(reader.tabID);
+			
+			let { tab } = tabs._getTab(reader.tabID);
+			assert.equal(tab.type, 'reader-unloaded');
+			assert.lengthOf(tabs._history, historyLength);
+			tabs.close(reader.tabID);
+		});
+	});
+
 	describe("Window teardown", function () {
 		it("should not leave observers registered after a window is closed", async function () {
 			this.timeout(60000);