Can the read/seen state be shared with my colleagues?
In Missive, each user has their own (un)read state.
When reviewing conversations your coworkers are working on, seeing conversations you haven’t read, highlighted in blue, can help quickly target which conversations should be reviewed now VS those you have already reviewed. Also, when you select any conversation, regardless of your own read state, you can quickly see if coworkers have read it themselves by looking at their avatars at the top:
Here you can see a coworker (light green background) hasn’t read the conversation because of the little blue pin, whereas the other has read it.
Keep in mind that the primary way to triage and clean team inboxes is to assign/close conversations, not to mark them as read.