You are many to join #Fedilab. We will improve the UX for adding several accounts. We have been warned about this issue.

If you have several accounts, Fedilab has an interesting feature for you.

Just long press action buttons (boost, like, bookmark, reply, follow, etc.)
That will allow you to finish the action with another account without switching.
The app will do everything in the background for you (search, federate, do the action). So you will never lose what you were doing.