I seem to have encountered a new fault with stone images in the last few days. After stepping through what appears to be a small fixed number (moves 54-55, 59-60, 34-35) of moves in game review mode (seems consistent for each game being reviewed) the stone images spontaneously change across the whole board to very different images (just small flat drawn circles).
Plausibly this could be the stone images disappearing at this point and displaying a more basic underlay. Changing the stone design settings normally immediately changes the board stones, but once this occurred has no effect.
This is on Windows using the Edge browser.