This just showed up on our forum, is it a new “feature”? How can it be disabled?
AI-generated summary
Users on a Discourse forum noticed a new “switch button” appearing in the chat sidebar, prompting concern and questions about whether it was a new feature or a bug. hello-smile6 first reported it, sharing a screenshot and asking how to disable it. twofoursixeight and Firepup650 confirmed it was appearing across instances, including Meta, and suggested viewing in mobile mode to reproduce. hello-smile6 linked a recent GitHub commit, suspecting it as the cause. j.jaffeux acknowledged the issue, explaining that the commit had been split due to problems and that fixes were imminent. In response to requests for a temporary workaround, j.jaffeux provided CSS code to hide the button: .sidebar__panel-switch-button { display: none; }. hello-smile6 expressed relief, having initially thought it was a prank. When asked if hiding the button would restore visibility of non-chat sidebar sections during fullscreen chat, j.jaffeux clarified it wouldn’t — but noted a fix for that was already merged. hello-smile6 asked if the old layout would return, to which j.jaffeux confirmed the default would revert to the previous design. j.jaffeux later indicated the issue should now be resolved, though he was still addressing related bugs. The community appreciated the quick response and transparency.
Looks like a new feature on Discourse to me
I can reproduce this on Meta as well, so something is happening.
Note: If you can’t reproduce it, view the forum in mobile view, then open the chat
Is this what broke everything?
https://github.com/discourse/discourse/commit/b2b84cc957367c467ec28b70af9c0e392ee8ecab
Wow you are already running it 
There’s been some issue and the commit has been split in two. Should be fixed in the next hours
Is there a way to disable/hide it for now (maybe with a theme component)?
Add this to your theme:
.sidebar__panel-switch-button {
display: none;
}
That’s nice to know (at first I thought it was a staff prank, and I was confused when I didn’t see anything in logs)
Will that make the non-chat sidebar sections visible when chat is in fullscreen?
No, but the fix for this is already merged.
Im still working on few bugs reports about this right now, so it’s possible there are more fixes in next hours.
Will we be able to use the old layout eventually? I tend to check whether there are new messages in specific channels while reading posts, and being unable to see the channel list while looking at topics makes that impossible.
Yes the default will be as it was
I think it should be good now.