I've had several users raise issues about being able to keep track of messages and flag ones they want to come back to later (they know about "Save") and I wanted to offer them the advice to mark messages unread and use the /unread command to call them back up later in the day. However, testing this behavior, it doesn't appear that a message you've manually re-marked as unread will show up.
Steps to reproduce:
Find a post that you are tagged in or that's in a channel you've set to show notifications in your feed
Hit the three dots in the upper right of the post and select "Mark unread"
Enter /unread in the command box at the top of the Teams application
The message you've marked unread does not show up
The channels where I have tested this do appear in bold, indicating that I didn't accidentally read them again before testing. Additionally, if I manually filter my feed to show unread posts (instead of just using the command), they don't show up that way, either.
Is it intended behavior that the unread filter and /unread command do not surface messages you've manually marked unread? If so, why would it be designed to work this way?