This is excellent, and very helpful.

One suggestion I'd like to make (I don't know how to code it or I would, sorry): is there any way to implement a "snooze bar" that you could use once that would give you an additional, configurable, amount of time before starting the block period?

I find the transition is too abrupt when I access a page and all of a sudden the block is on -- it tempts me to turn the script off, and that's not good.