If the preference "Group changes by page in recent changes and watchlist" is enabled, then all Flow edits get the red exclamation mark indicating "unpatrolled".
(See screenshot, where Quiddity's edit to the "Loveless" topic should have been marked as patrolled, as it was in the Project:Sandbox)
If that preference is turned off, then no Flow edits get marked as needing patrol. (All edits by editors who are not in a group that is "autopatrolled", should be marked as needing patrol, if a wiki is configured to use that.)
See mw:Help:Patrolled edits for details.
To know whether a page should show the 'Mark as patrolled' link, we need to store a mapping between the Flow revision and the RC table (the RC table currently points to the Flow revision, but not in a way that can be queried).