"As paradoxical as it may seem, defending intolerance requires to not tolerate the intolerant." [i.redd.it]
Yes but you can ignore the crap out of them, thus maintaining tbeir right to be an asshole while having some integrity.
"...defending tolerance requires to not tolerate the intolerant."
not
"...defending intolerance requires to not tolerate the intolerant."
In general I agree with Popper but I think there is a large gray area, which again is used by the intolerant to their advantage.