In my view, the key thing to understand is what Popper actually meant. If you read the actual quote from Popper that is the origin of the idea, by "the intolerant" he didn't mean people whose ideas were intolerant. He meant people that answer ideas with fists or guns. That level of intolerance you cannot tolerate.

When you run into people who are X-ist (for a very large range of values of X), answer them with discourse. When they make a fist or reach for a gun, then you can't just talk any more.