I was wondering about some kind of memory leak. On the few occasions I've bothered to check, Firefox is hogging several GBs when the problem occurs.  I've only recently started trying Firefox with Android and still (rather lazily) just use Chrome as that's what the phone came with. I'll try it a bit more.

The only time I see it is on Android when I'm using Twitter. But then I don't really venture outside the few sites I like.

Making the most of your retirement, eh?

I spent far more time on the internet at work.

Don't use ABP, use uBlock Origin. (Whatever device or browser you're on.)

Also consider uMatrix to block all scripts and resources and then selectively enable only the ones you need. (It can be a bit of a pain when visiting new domains, but it helps massively with preventing unnecessary crap from clogging your browser+connection and you soon get used to figuring out what's essential/useful/unnecessary when a site doesn't work.)

I switched to ublock a while ago and find it a tad aggressive, and the ui isn't very intuitive.

Haven't yet worked out a quick and simple way to add a site to a white list, or to selectively re-enable elements on a page.

Change your filter selection if it's too aggressive.

Four clicks to get to the Whitelist section might be annoying if it was a regular feature, but I think I may have used it once or twice tops, so... *shrug*

If it bugs you that much: https://github.com/gorhill/uBlock/issues