The yelling trigger i have is because if someone yells at me directly, and it starts hitting other trigger points, such as depression, anxiety, insecurity, ect, then i get triggered and nearly have a mental anxiety attack, causing me to temporarily delete my emotions so my brain can "reboot." If i hear yelling from a movie or a show or anything else then im ok with it. As long as its not directed at me.
Now, if someone if yelling at my mom, yes, i will get triggered but nothing is triggered besides my hothead self. My hothead self is a complete total insane person that if i care about someone a whole ton, even if they make me upset, and they get yelled at or upset, chances are im going to my bed, pissed off, wishing i could scream at how disappointed I was, and yes that does spark my toxicity self so i may be a hypocrite and a rude moron for a bit until I calm down.
But yea, just dont yell at me directly, or someone i care about a ton, (like my mom. I hate it when my dad yells at her...she doesnt deserve yelling for almost no reason) and we might be on good terms. :>

however if you trigger me a ton
Welcome to my hothead personality to where i dont give two craps about you :)
(Only for people on my bad side)