Is there a way to do this without using delay?
I found some code to blink without delay, using millis, but I couldn't figure out how to incorporate random into that, without it seeding random every time.
I also couldn't figure out how to make the random blinking toggleable on and off, while using millis.
Ideally, I want an on/off switch, to be able to engage a random blinking, without using delay (I'm using values up to 500ms, and don't want everything else on hold while that's happening).