Hello,
I am running windows 11, and had to update my username as windows truncated to 5 characters.
I successfully followed the following guide to update the username:
https://www.elevenforum.com/t/change-name-of-user-profile-folder-in-windows-11.2133/
However, once the username updated it broke my dropbox install pointing to the old username, I uninstalled dropbox and reinstalled.
But when I tried to login I get the subject message and browser doesn't pop open to allow for input of username and password. 