Friend: [over text, after sending me a picture of an outfit they had on a few days ago]
$thing is one of your triggers, right?

Me: [taking deep breaths while trying not to think of anything while texting back, feeling my heart rate spike]
Yes, $thing is still one of my triggers.

Friend:
Oh, okay, cool. I had a picture of $thing from last night, so I figured I should check with you before sending it. Glad I remembered right!

Me: [thoroughly spiraling, triggered]
Yeah.. Thanks. 🙃

Friend: [radio silence]

PSA: Check in with how your friends are doing before asking them to list of their triggers. For maybe obvious reasons. When they're feeling good, ask them how they'd like you to address content around their triggers (warn you, discussion okay but not photos, etc).

Once you're finished discussing potentially triggering content or have accidentally brought it up, consider changing the topic to something nice to help draw their attention elsewhere for a while.