Hey everyone - here's an easy place to reproduce this bug: Google's products!
Go to Gmail. Open the sidebar where the calendar lives. Now try to add an appointment, or modify an existing one, or whatever. Especially if you invite someone to said appointment. You will be totally unable to use the sidebar. No cancelling, no saving, no nothing. Same issue in all Google products: drive, docs, sheets, etc.
Very frustrating. Please fix!