A bug has been reported regarding this: "I changed browser.tabs.tabMinWidth to something larger than 100 and opened enough tabs so that the width of browser.tabs.tabMinWidth was reached, played audio from one of the tabs

Actual results: the tab with audio playing icon shrunk...

Expected results: browser.tabs.tabMinWidth should have been adhered to."

Hello

Take a look at https://www.reddit.com/r/FirefoxCSS/comments/1j4f0hs/how_to_stop_this_new_tabshrink_animation_when_a If you wish to test userChrome.css /* prevent audio playing tabs from modifying tab width */

https://www.userchrome.org/how-create-userchrome-css.html

I've already tried but no change.

Other topics have been created about this. (but everything is scattered: connect.mozilla; bugzilla.mozilla; support.mozilla; ...) :/

I hope it will be fixed soon!

https://bugzilla.mozilla.org/show_bug.cgi?id=1952080 https://techissuestoday.com/firefox-v136-mute-tab-change-driving-you-nuts-heres-how-to-revert-it/

My previous answer is gone...

I had tested a similar code without effect but this one seems to work around the bug. Thanks!

I hope it will be resolved quickly, that we don't have to tinker ourselves! ^^

You need to also post what site is causing this as well as what userChrome.css your using and if css edit you should post that to the site where you got the userChrome.css to address the css issues.