> uBlock Origin.

I did try this without success.

> if the whole UI is irredeemable, you can access your mail with IMAP or POP.

I access my mail across a doz machines - and I support scores of users. Setting up stand-alone/3rd party clients (at scale) is a bit unwieldy.

The bad actor here turns out to be the Chrome browser. Every other browser behaves better in this.