When a friend changes their style, music or beliefs, ask about it before you joke about it.

A change like that is usually a person trying something on in public, which takes more nerve than it looks. The first reaction they get teaches them whether you are somewhere they can keep changing. A joke lands as a verdict even when it is affectionate, and it tends to end the experiment early. A question does the opposite and costs you nothing.

Ask what they like about it, and mean the question. You do not have to agree with any of it or adopt a single thing yourself. Save the teasing for a year from now, when it has stopped being fragile.