When closing the last chat tab. It should open up a New Chat tab instead of collapsing the entire right panel, which can be done manually by clicking the top right x button or the panel button.
Maybe if the last tab is a New Chat tab and it is closed, then the entire right panel could collapse since that appears to be the user’s intent. Otherwise, I often like to close old chat tabs and right now I have to open a new one before closing the last one, which seems unnecessary.
Same feature request: Closing all chats should open new empty chat