Have you tried Firefox? It's the only browser not based on Chromium, so it's unlikely to have this issue.
I understand you've tried removing all event sheets, did you also remove all scripts?
Instead of removing all event sheets, try creating a blank layout with no event sheet attached.
It may be a big job, but as an experiment you can also copy all your layouts to a blank project and see if it still happens there. Maybe the problem is caused by something like a corrupted font or audio file.