Yeah, that is my understanding, too. Otherwise you’d only want to generate them on the database host, as even with NTP there will be small differences. This would kind of defeat the purpose of UUIDs.
If you’re saying that even without NTP, just by manually setting the time, things will be fine. I mean, maybe. But I’ve seen it far too many times already that some host shows up with 1970-01-01…
I’m using Simon Tatham’s Puzzles for nonograms.
It’s basically this webpage in app form: https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/pattern.html
It doesn’t result in a pixel art picture when you solve it, if you care for that, but the solutions do have contiguous regions.