Too bad it needs Java.
slikts
You’ve set up a dichotomy between limited (e.g., reciprocal) tolerance and absolute tolerance by presuming that the limitations would be arbitrary and unjustified, but the limitations are justified by self-preservation (in case of Popper, tempered by preferring rational discourse if possible), so what you’ve said is an illustration of the fallacious argument this question is about.
The closest existing label turns out to be absolutism fallacy; I’ve posted a more focused question about the same topic elsewhere.
Presuming justified exceptions to a principle to be impossible is what makes something an absolutism fallacy in the category of fallacies of presumption.
Applying moral principles to the real world requires complex reasoned judgement. Making the principles pure or absolute is an attempt to make the required judgement formulaic instead, often due to a cynicism about individual judgement abilities of people, and this wittingly or unwittingly leads to a paradoxical outcome like in the paradox of tolerance.
You can use a simple bookmarklet to make links on LW non-functional, e.g.:
To use this you would just set up a bookmark with the code as the address and click on it while LW is open.
Edit: A cross-site version of the bookmarklet would look like this: