Split-screen/Tab-in-Tab feature (view more than one tab at once)

[KERR]

Currently I'm doing research on a heap of products, and collating into an online spreadsheet. I'm wearing out the Ctrl+Tab keys flicking back and forth, copying/pasting etc!

It would be awesome to "pop-out" a tab and have it "float" on top like what Picture-in-Picture does. I know you can the tab in a new window, resize it, move it etc but it still doesn't stick on-top and has borders that take up space.

I've seen extensions that try to do split screen for tabs but they don't seem to work very well. Thanks!

[Jon]

(Note: similar ideas have been merged into this thread)

[Rinzler]

Screen Splitter

A button located on the toolbar that allows you to split the screen in two and have two tabs on the same screen (similar to the option currently available in Edge). This would let you view two tabs simultaneously, providing greater comfort and productivity.

[Jon]

(Note: similar ideas have been merged into this thread)

[asafko]

Hi folks, 

Split View feature is now available for testing in Nightly to all users with no restrictions and no pref flipping.

How to test: Update to the latest Nightly and see the attached this handy demo for basic Split View interactions. 
Where to report bugs and give feedback: We are actively polishing and testing the feature, so there's a good number of already known bugs on file. Some of the things you may notice almost immediately: 

• We have not yet started persisting Split Views in session restore. Until this ticket lands, when you restart your Nightly, your Split Views will restore as two standalone adjacent tabs. Once it lands, your Split Views will be restored as Split Views. 

How to report issues: Please file a Bugzilla ticket in the Tabbed browser - Split View component if you find a new issue (we would appreciate it if you could peek at the Bugzilla bug list first to ensure this isn’t a duplicate). If you have general feedback, please post it here as usual. 

When: We’re running community testing through January 15th (you're welcome to continue testing and reporting issues after this date), and we plan to make the feature available in the release channel in Firefox 149 (March 2026).

[tilwiti]

💐🎉 @asafko 

[Locolau]

Thank you so much and great for implementing this, I will do some testing!

[yshavit]

This is great!

I have three related pieces of usability feedback:

1. When inactive tabs have the‌✖️‌close button, each split includes its own close. This makes it too easy to accidentally close the left split when I'm trying to click to activate that tab (since the left split's ✖️‌ is in the middle of the tab).
2. It's a bit unitintuive that the ✖️‌ button only closes one of the splits. I think of the ✖️‌ as applying to the tab, not each of its splits. (That said, I can definitely imagine someone else preferring the current behavior. Can't win 'em all! 🙂 )
3. When I do close a split, and then try to undo the close, it opens it as a new tab. I'd like it restored to the split it came from.

The first one of those is the biggest for me — the other two are basically downstream effects that I suffer from regularly because of the first.

But again, this is great. Thank you for it!