[FEATURE]: Vertical tabs

[SkyElianneLavoie]

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

The new UI forces horizontal tabs, which make it really difficult to see more than 5 session titles at once.

I really wish we had a way for the tabs to be horizontal, similar to how the sessions were shown in the old UI.

Vertical tabs are a really popular feature amongst programmers, so this feels like a no-brainer!

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• Desktop: wtf is the new tab layout, tab titles dont fit anymore on screen #36936: Reports the same problem with the new horizontal tab layout making it hard to see session titles, and explicitly mentions vertical tabs as the preferred solution.

[w1321630350-tech]

是的，之前我只需要两步，现在我需要三步，我希望标签页水平排列

[frederikhors]

Please this new horizontal tabs kill Opencode Desktop! PLEASE REVERT OR ADD A SETTING! PLEASE!

[developerzeke]

I was very sad to see that the old layout will be discontinued. I don't love the tabs, I'd rather have it all separated by project and using vertical tabs so I can read more of each chat's name. I'm a horizontal tabs guy in smth like chrome, but in an AI chat interface I want vertical tabs separated by project.