I noticed this issue starting on Friday. Whenever I tried to edit my spells by "Unlocking" them to delete them Roll20 would stop responding. Today while playing the issue persisted and also occurred whenever I would roll Initiation, Hit Die, or any kind of check. Damage and hit on spells were unaffected. This issue happens in all games I involved in with all characters. My Chrome Version number is 54.0.2840.71 m and apparently I have an update to apply. I currently run Windows10 I'm going to update Chrome and post back with what happens.