Hi,
Currently, when I click on the hamburger menu (top-left) in the Thunderbird Mobile on Android, it displays the list of folders and subfolders of the account I am on, starting with the main ones (inbox, outbox, archive, etc.).
However, when it comes to my own subfolders, the displayed name is very convenient: when folder A contains folder B, folder is listed as "A.B" and vertically aligned with folder A.
It would be much cleaner and easier to visualise to call it "B" and to add a small horizontal increment, so that the name "B" would be a little bit more to the right.
Thanks!