User blog comment:MisterWoodhouse/The first migrations to the Unified Community Platform/@comment-24.23.186.90-20201106221047/@comment-26339491-20201109172329

Comment data is not lost. There can be occasional hiccups during migration that prevent comments from showing up, but the data is there. If your wiki has been migrated a week ago and you still don't see the comments you know should be there, please let us know via Special:Contact with a link to your wiki, so we can run the script there again and make the missing comments show up.

If you're seeing security flaws, please also let us know what those are, exactly, so we can address them! Currently we're not aware of any open issues around security (i.e. anything that could expose sensitive user data, make accounts hackable, allow troublemakers to insert harmful code into pages, etc.), but when we do become aware of something of that sort, we fix it very quickly.