How can I have all my email accounts in seperate tabs and act separate?

Question

I am trying Thunderbird again, and what seems like an intuitive way to organize multiple accounts doesn't seem to work for me. I guess that means it's not possible? I checked out the extensions and did not find find one to address this issue.

I'd like to have multiple email accounts in Thunderbird, and each one displayed in their own self contained tab.

Currently, the folder tree all on the left seems to be related, even across tabs, such that if you expand or contract some folders in the other account, when you switch to the other tab, the same operations have been performed.

If you have the different accounts open in separate windows, they are completely separate like I would like, but then I'd need to keep track of different windows. Part of the reason I am moving to Thunderbird is to reduce the number of windows I have open, so that's not ideal.

Is this a bug or a feature? Is there a way to get it the way I want?