How best to deal with a post to meta of this sort? There are two issues: it doesn't belong on meta, but at the quality level of the post, it doesn't belong on main, either. One alternative would be to migrate the on-hold (current status) to main, as an on-hold question on main. But if it hadn't yet been put on hold, what's the best action a reg. ole user like me can take: flag to migrate to MSE, or close on the spot?

@amWhy Exactly what has been done. Vote to close as off-topic with the "it's a mathematical question" reason. Either it will be re-asked (hopefully in better form) on main, or not. Some time after closure (give the author time to read the close reason) it can and will be deleted on meta.

@DanielFischer Thanks, good to know.

Is it worth flagging if a user repeatedly (3 times today) posts a dummy answer, deletes that answer immediately, and later replaces it with a full answer (and undeletes it)? Or should I not care about that FGITW behavior?

@amWhy No, there were no more reversals

@an4s This would be good to check in with a mod, like @DanielFischer, about. I don't know how many were not reversed, but I think you have a valid concern.