Thunderbird does not delete messages from the POP server.
I am a Yahoo Plus user and I can download messages from the inbox in Thunderbird from the Yahoo POP3 server.
However, I want to delete read messages directly on the email client rather than go to Yahoo Mail. When I do this, emails are still on the server
In accounts setting, I have the following options ticked:
-Automatically download new messages -Leave messages on server, Until I delete them
Update: Thanks for the replies so far. Some clarification: I do want to keep some messages on Yahoo for filling them in my online folders, hence the reason I do not download ALL my messages to Tbird and delete server message automatically