Ooo, this is a cool feature. #Firefox users are going to love it. It's been in #Vivaldi for a while now, and it's super useful. I use it a lot, especially at work where I'm copying information from a ticket or something into a web form.
https://www.omgubuntu.co.uk/2025/12/enable-firefox-split-view-feature
@mike its been in #zenbrowser for a while as well, but I very rarely use it. I guess it depends on your habits and workflow