If not, and you go to Tools → Developer → Run JavaScript and run the following command, does it happen again on the next startup?

(The reader doesn't run any page JavaScript, so this is probably a CSS issue, but we'll need to see the file to be sure.)

Substack does capture copy event with javascript for a pop-up to "Restack". Maybe the snapshot has preserved part of the javascript so it still captures the copy event but does not bubble the event up

[JavaScript Error: "HTTP GET https://eutils.ncbi.nlm.nih.gov/entrez/eutils/efetch.fcgi?db=PubMed&tool=Zotero&retmode=xml&rettype=citation&id=40015819,39991680 failed with status code 0" {file: "chrome

After launching version 7.1-beta.17, I see a "'value' must be a string" error:

https://forums.zotero.org/discussion/121777/javascript-error-the-user-aborted-a-request-in-zotero-desktop-version-7-0-11-64-bit

When I try to set up WebDAV sync I see the error: [JavaScript Error: "The WebDAV server did not accept the username and password you entered. Please check your file sync settings or contact your WebDA

When viewing and annotating a PDF within the app, converting an underline to a highlight generates some kind of javascript error (report code:297722493). At this point the tool bar vanishes and the ri

[JavaScript Error: "[Notero] Starting v1.0.0"]

in months. Did you disable automatic updates? [JavaScript Error: "Zotero.Utilities.xpathText(...) is null" {file: "chrome://zotero/content/xpcom/style.js" line: 651}]

[JavaScript Error: "Missing property "translatorID" in translator metadata JSON object in undefined

[JavaScript Error: "Error 400 for item TSZFKR8F in Ma bibliothèque:

that import, and run this code in Tools → Run JavaScript to delete all the invalid creators:

[JavaScript Error: "uncaught exception: undefined"]

-> The toolbar has disappeared. [JavaScript Error: "annotation is undefined" {file: "resource://zotero/reader/reader.js" line: 25346}]

After selecting the snapshot, it shows the following error in the Debug Output: [JavaScript Error: "Failed to attach Declarative Shadow DOM."]

[JavaScript Error: "Download request 1/BD39ZKTB failed"]

[JavaScript Error: "Calling -setData:forType: on NSPasteboardItem with nil `data` for type dyn.ah62d4rv4gu8ycyc2mu. @[setText:field.m:395]" {file: "resource://zotero-macword-integration/messagingGener

[JavaScript Error: "HTTP POST https://api.zotero.org/users/16398750/fulltext failed with status code 400:

You can just select any potentially affected items (e.g., sort by Date Added and select all the items you imported from the RIS file at that time), paste that code into Tools → Run JavaScript, and cli