If you're doing more than you're supposed to do, or doing things outside of normal work time, no matter what DOCUMENT IT. If they're a good employer, they'll compensate and reward you, if they're a bad employer you can leave and it'll be easier to update your resume by referencing your own documentation
The fact that "don't work off the clock" and "don't do work you aren't getting paid for" are genuinely needed bits of advice rather than absurdly obvious common sense should radicalize all workers.
yeahh, society preaches loyalty to your company first rather than loyalty to yourself and your health first. It's unfortunate. I will say, I love my team at work, and if it'll be good for the app we develop and its a very rare instance where we crunch to get something done, I'm willing to do that. But that's only because it's not common and because my team is good and my employer is decent. If it were a company that were shitty to me, I would not put in the effort unless I was in danger of being fired and I desperately needed the money, and even so I would be actively searching for a new job.