I tried this out in beta and could not reproduce your particular problem.
I did however notice that the Submit button shows strange behaviours.
It shows both on the last played move as well as on the not-yet-played move. Since you cannot see what you are submitting when the board shows the actual current position, I’d say that the button should be available in the latter case only.
When it is not your move, the string “[White|Black] to move” is shown to fit the currently displayed position, i.e. if you go back in history to a position where it is black’s move, it will say “Black to move” and vice-versa.
One could argue that the proper behaviour would be to show whose move it is in the actual board position, not whichever past one you are currently viewing. But that is only a minor point.
As long as you have not pre-played (set without submit) your own move, the display correctly says “Your move” on the current turn and “[White|Black] to move” while navigating the game history.
Then when you set the stone (before submit), it displays “Your move” - still correct.
But once that stone is there, navigate anywhere in the history (even back to the current move again) and the only string shown will be “White to move” if you play black, or “Black to move” if you are white. If it is your own colour’s turn in the displayed position, the text will simply disappear until you navigate on.