I don’t have the answer, but if you are looking to do something like that you could simply do :
if coin in (25, 10, 5):
Or use a list but I think using a tuple is better as your values are fixed.

IMHO it’s just that you had problems with your firefox installation. Probably if you had tried a new profile or reset it using troubleshooting menu it would have been the same.

My reco for OP is to try troubleshooting information to clean your profile.