Rules for from account in Apple Mail I happily use mail with several accounts. When I send a new email I often forget to choose the correct 'From' account. Is there a mail plugin that allows to set the default 'From' account using some rules.

One example could be: if the recipient ends in '@example.com' use the work account.

Or as an alternative is there a way to change the 'From' dropdown menu using a key combination? (this would not solve the case when I forget to set it but would at least speed up the process)
If you use the unified inbox then this can be a problem. If you expand the mailboxes and read them from those, then you can set-up Mail to send using the account for that mailbox.

I suppose this may require remembering to select the correct mailbox in a similar way to remembering to select the from account though.