I always make sure i can code on Vacation on my own projects. The flipside of this is tho: i never take time off, since my work is rather relaxed anyways.
My employer messages me about that recently, that i still have 100% of my vacation days left, so what i did is using it all up until the year is over. Essentially im almost all the time on vacation until the end of the year (+ a little), and can work on my own projects. One rust project might be in a publishable state soon actually.