This happened to my dad when he upgraded the other day and I spent hours painstakingly trying to fix it and it seems like the recommended fix is reinstalling OS

This happened to my dad when he upgraded the other day and I spent hours painstakingly trying to fix it and it seems like the recommended fix is reinstalling OSX. Well, he's on Firefox now but what the fuck - this basically affects all the websites he goes to. I can't believe this made it out through testing.