Download various Linux distros. I’d use torrent that doesn’t have download or upload throttling, and grab several Linux like Ubuntu, Knoppix, etc and start em all when you’re trying to connect to Whatsapp. It’ll act like you’re using an ancient 56k dialup.

Or if you happen to know of local ISP that still uses dialup, use that.

Only works if it’s not a built in keyboard for laptops.

Or a separate computer just for the screensaver and use some type of switch with 2 inputs to share a monitor. A Pi is cheap enough to be used for looping video or slide show

Delete cookies and clear cache. Then log back in and try again. It sounds like cookie file got borked somehow