It's working fine for now :) The blocking button now has a different look. Instead of a cross, it has a circle with a line through it, which looks even better.
However, it's difficult to see; it's dimmed and becomes more visible only when you hover over it.
The rest is the same as the old channel blocker.
You can even import the list from the old blocker.
I hope it works as long as possible, because it's the best YouTube channel blocker I've ever used.