A calm “what do you mean by that?” stops a lot of fights before they start.

Most fights are built on a guess about what the other person intended. Asking what they meant, in a flat and genuinely curious voice, takes your guess out of the gears and makes them say it again in plain words. Half the time the plain version is milder than the one you had already begun answering.

Try it the next time a sentence stings, before you reply to the one in your head. Keep your voice level, because those same words delivered sharply become a challenge instead of a question. Then actually listen to what comes back.