My game (http://lichess.org/poxzeq70) started before the big lichess upgrade on April 28. It was my friend's move. After the big upgrade, my friend has twice thought he's made a move, only to have
the game revert to the pre-April 28 game state. I'm inferring this from the two emails he sent me, letting me know that it was my move. In the second he said "sorry i thought i had sent the move, but
it should be really sent now". It's still his move (or his move again). Would it be simplest to end the game? Or would it be a useful corner case for code testing? I'll further test with a reserve
game (http://lichess.org/fhrak8ek) that was also started before April 28 (it was my move; now hopefully his move).

My friend tried again. Apparently, even in the session, the piece moves without triggering the change of move. The right side panel will still say that it's his move. Strangely, I managed to move in
our reserve game. That game's also messing up for him. I can't report the phenomenon firsthand. We're both happy to keep the games around for testing. We'll probably start a new game, and see how that
goes. The game state revertion might be caused/affected by something other than the date of the (site upgrade) / (game start).

When I used to have this happen to me in games I played, I fixed it by refreshing, until thibault rewrote the site such that I no longer needed to refresh anymore.

I suppose it's possible some people may still need to.

If refreshing the page to see if, then, the updated move shows in the game, hasn't been tried, I'd test that out.

Refreshing didn't work. We're starting a new game. We'll keep the old games open.