Interesting, from the doc[1]: "Because of various issues Invidious must be restarted often, at least once a day, ideally every hour."
[1] https://docs.invidious.io/installation/#post-install-configu...
I guess it's related to this issue, a memory leak (or probably multiple): https://github.com/iv-org/invidious/issues/1438
Also interesting that the issue is almost 3 years old and mentions even older reports.