You can activate Mission Tracking that tells you when a tracked mission is available.
Is there any chance to also track whether a tracked mission is completed and awaiting pickup? Blizzard's mission icon is a mess, and once you're levelled past an expansion you no longer have the flashing icon on the minimap to help remind you that you have a mission to pick up.

Being able to at least get a notification for important missions (ie ones you've chosen to track) would be super handy.

Take a look at Mission Report Button Plus: https://www.curseforge.com/wow/addons/mission-report-button-plus