Shopify does this. If you ever go to purchase a product on a Shopify 'site, and enter eg your e-mail address, it'll save it even if you decide to cancel and close the tab. Sometimes you receive spam from companies along the lines of marketing or "we noticed you didn't complete your purchase" type crap. Shit is rly invasive.

HotJar and similar services are (were?) popular as well, and those record your mouse pointer movements and clicks as well, then displays that as an overlay over the application, so it's essentially a "screen recording" of your session of the application.

Yes, but codepen is for frontend devs. And devs are more likely to accidentally leak secrets because, well, they have them

Edit: accidantlay -> accidentally