User Agent: Mozilla/5.0 (X11; Fedora; Linux x86_64; rv:90.0) Gecko/20100101 Firefox/90.0

Steps to reproduce:

1. Open multiple tabs and windows of Firefox
2. Copy a text from Firefox to another program

Actual results:

The poragram where you are trying to paste the text just freeze for a couple of seconds and the text is not pasted

Expected results:

The text should be pasted without freezing the program

The Bugbug bot thinks this bug should belong to the 'Core::Widget: Gtk' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Can you try latest nightly with async clipboard enabled (https://bugzilla.mozilla.org/show_bug.cgi?id=1725149#c5)?
https://fedoraproject.org/wiki/How_to_debug_Firefox_problems?rd=Bug_info_Firefox#Testing_Mozilla_binaries
Thanks.

I'm running Firefox 91.0.1 on Wayland, and I cannot reproduce this. Copy-paste works fine here, with no delays.