Simple, realitively easy to use once you figure out to use the "Block domain and all subdomain" setting. Works really well to block unwanted websites. Only thing holding me back from putting 5 stars is that it would be nice to have a password lock option to prevent unwanted changes to the block list.

Tried to block youtube and twitch, it worked. However, when I tried blocking instagram, it doesn't. Dunno why...

A simplistic Website Blocker. But I would love if it had an option to visit the blocked websites without having to deactivate the whole add on.

Would be better if it could actually block URLs rather than act as an internal redirect. If I wanted a redirect, that's what I would have searched for and installed.
*Update: Since the Dev is actively working to improve and add new features, I'll boost my original rating. I realize development is a process that takes time. I'll give it another try when I get some time to do so. Until then, good luck with the add-on.