Until I delete them

This question has been asked many times in many places but no solution actually works for me. I have a Windows 10 desktop and various other devices. I originally set up my POP gmail account so that emails were kept on the server until deleted from the Windows desktop. In this way, I could access them from all my devices but automatically remove them from the server by deleting them in the desktop. My server settings in TBird on the desktop were: Leave messages on server Until I delete them On the other devices, I just left the messages on the server forever. This worked well until about a year ago. Now, no matter what I do, I can't get TBird to remove an email from the gmail server. I updated TBird several times, used all the combinations of server settings, edited a couple of the advanced options (mail.pop3.deleteFromServerOnMove, mail.imap.expunge_after_delete [even though I'm not using imap]) but nothing works. Did there used to be a mail.pop3.expunge_after_delete which has been removed ? Not being able to automatically delete on the server has many non-trivial side effects. Does anyone know of a solution ? Thanks Gerry