Last session while I was running Princes of Apocalypse, I experienced this weird bug. Everything would work fine for a little while but then whenever a player would try to move their token (or indeed merely clicked on the token), the token would instead zoom into the nearest wall, and then be stuck there like a magnet (as the DM, I could see that they were stopping at the border of the lighting layer). I, the DM, could move the token back into place and it would stay put, but whenever a player would try, the same thing happened. Only reloading Roll20 would fix it, and only temporarily. Anyone who's experienced this know how to fix it?