Earlier quoted context omitted.
> However, I hate using tabs in the browser, so thanks to a hacky extension, firefox opens a new window per tab, which means that i3 manages firefox' tabs as regular windows. Can you provide a bit more information about your setup? I'm using sway and I removed the tabs from Firefox to handle them as individual windows.
I don't have my machine on hand to give you the specific extension, but basically it's something called "notabs" or similar. Whenever a new tab is opened, it gets moved to a separate window. It works mostly OK, but it can sometimes get confused. I combine this with some custom chrome to completely hide the tab bar area at all times. Afterwards, I manage my firefox windows with i3 as I would any other window. They usu…
https://addons.mozilla.org/de/firefox/addon/adsum-notabs/
For the custom chrome, I'm using in userChrome.css:
#TabsToolbar { visibility: collapse !important; }