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When a reply is posted on a root post that has a mention, the mention badge stays on the channel that has the root post, BUT the Threads view now displays as bolded with a new unread message in a thread you follow
Marking Channels as unread vs. Marking Threads as unread
Marking a thread as read/unread will NOT have any effect on the Channel’s sidebar state
Opening a channel, marking posts as ‘read' will NOT have any effect on the Threads' sidebar state
Other Implications to existing features (webapp)
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