AdBlock on mobile is a Firefox great advantage that everyone can appreciate. You can install it with AdBlock on mobiles your friends and family uses.
This is a great feature. However, the UX is super bad.
I use Firefox for desktop for many years know and I'm happy with it. But for mobile, I keep it installed (and use it from time to time) just to support it.
https://news.ycombinator.com/item?id=38210671
At a much lower power level, I had a couple harrowing experiences with powerful industrial grade table saws (4 to 5 HP spindle). In one case it grabbed this piece of plastic being cut and launched it 25 feet at such speed that it penetrated the door of a refrigerator that just happened to be in its path.
You can never take powerful equipment for granted. And, if it is computer controlled, well, make sure you can see the power cord being disconnected before you even think about getting anywhere close to parts that can hurt you.
One of the things I taught my kids when doing projects with power tools at home is to unplug the cord after you are done cutting/drilling/whatever and place the power plug right on the machine where you can see it. With time you get used to not approaching the machine unless you know where that plug is...in the wall or on the machine.