From cc3fc42b0ab740d139b301089937608d4aa1f130 Mon Sep 17 00:00:00 2001
From: Abe Jellinek <jellinek@berkeley.edu>
Date: Tue, 5 Aug 2025 11:17:03 -0400
Subject: [PATCH] Catch BlockingObserver error when reader is closed
 immediately

https://forums.zotero.org/discussion/125841/cannot-open-a-pdf-file-in-a-new-tab
---
 chrome/content/zotero/xpcom/reader.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/chrome/content/zotero/xpcom/reader.js b/chrome/content/zotero/xpcom/reader.js
index 5a0f78c8cd..4f8c07acb2 100644
--- a/chrome/content/zotero/xpcom/reader.js
+++ b/chrome/content/zotero/xpcom/reader.js
@@ -187,7 +187,13 @@ class ReaderInstance {
 				return uri.scheme === 'http' || uri.scheme === 'https';
 			}
 		});
-		this._blockingObserver.register(this._iframe);
+		try {
+			this._blockingObserver.register(this._iframe);
+		}
+		catch {
+			// Reader was closed before it could be initialized
+			// No need to log this
+		}
 
 		// Prepare Fluent data
 		let ftl = [];