The title should be "Bug with clock times" as opposed to "Bug with move times".

Have a look at the following game: (click the link below the board to see clock times) lidraughts.org/7Tp5jCSf/black#20
After black's 10th move (23-29), white's clock time is displayed as 8:32.6. However, after white's 11th move (34x14), white's clock time is displayed as 9:45.8. However, white's clock time cannot have increased, since there was no increment that game. Two observations I've made which may help track the bug down:

• The wrong clock time (9:45.8) is the same as the opponent's clock time;
• I've only encountered this bug on moves with multiple captures.

I have experienced a buggy clock in one of my games. The clock showed it's my opponent's turn and his time went down to zero because he was losing and didn't want to move. Then I saw I lost the game on time. Here is the game:
lidraughts.org/36tGoxTxsXsO

@MessyAnswer It has been fixed, movetimes will be rendered correctly after the next server update. Thanks for the accurate bugreport!

github.com/RoepStoep/lidraughts/commit/66631c39cbf0c569bbfb683d1eb1d0dc7689bd29

@RoepStoep Please fix the bug I have encountered. I saw my opponent's time going down and running out at the game's clock while in fact my time run out and I lost on time. I posted the game on #2 above. You can see that I lost on time during opponent's turn!

@Hangrad I'm investigating it right now

Thank you!

Pfew, that was quite the bug to track down, but it's fixed. It required very specific circumstances to show up, thank you for reporting! @Hangrad

github.com/RoepStoep/lidraughts/commit/ac5ba5f8d25e66144134dcd1fa7f0987076adba5

As this is a cricital bug (though very rare), I will update the server right away

And... it's gone :)