macosmail.app
I've enabled the builtin Mail rules to move junk mail directly to the junk folder. But the messages do not get marked as read, so they are shown/counted as unread in the Mail sidebar.
How can I mark mail that goes to Junk and Trash folders as read automatically?
Go To Mail -> Preferences -> Junk
When junk mail arrives, say: Perform Custom actions
Click on the Advanced button at the bottom, which just turned up to be active.
Then say "Mark as read" in one of your actions:
In case you didn't know, when viewing the different messages in the right reading pane, if you select any of the individual messages they will be marked as read. This gives you the ability to mark some as read and leaving others marked as unread.
Best Answer
For Junk Mail, you can create a Rule. From the menu bar item “Mail”, select > Preferences > Rules > Add Rule. Make a rule with the following conditions:
For Trash, you can simply bypass Mail’s Trash and rely on the server settings of the email account. To do so, from the “Mail” menu bar item (again) > Preferences > Accounts > [select account] > Mailbox Behaviors > uncheck “Move Deleted Messages To the Trash Mailbox”