That's a vulgar interpretation of Popper's argument, he was very explicit that he intended for his principle to be applied only in the presence of a serious and actual threat to freedom, not merely whereever such a threat would be conceivable.
>Less well known is the paradox of tolerance: *Unlimited tolerance* must lead to the disappearance of tolerance. If we extend *unlimited tolerance* even to those who are intolerant, if we are not prepared to defend a tolerant society against the onslaught of the intolerant, then the tolerant will be destroyed, and tolerance with them. — *In this formulation, I do not imply, for instance, that we should always suppress the utterance of intolerant philosophies; as long as we can counter them by rational argument and keep them in check by public opinion, suppression would certainly be unwise.* But we should claim the right to suppress them if necessary even by force; for it may easily turn out that they are not prepared to meet us on the level of rational argument, but begin by denouncing all argument; they may forbid their followers to listen to rational argument, because it is deceptive, and teach them to answer arguments by the use of their fists or pistols. We should therefore claim, in the name of tolerance, the right not to tolerate the intolerant.
The vulgar interpretation of Popper's argument justifies an eternal war of all against all, and defeats the point of ever discussing tolerance - group A correctly deduces that group B intends to use violence against their position, and so group A decides that violence is justified against group B; meanwhile group B is going through exactly the same logic, and together it's a self-fulfilling prophecy of an endless winner take all battle for the right to suppress everyone else's opinions.