Food in class
I've always found it really courteous of people who usually sit at the back/corner and eat or drink without bothering anyone.
But today, this guy sat in the middle of a silent class where only the teacher was speaking. He brought out his packaged food and was trying (and miserably failing) to tear open the crinkly plastic wrapper for a good minute and get his hand in it. It was annoyingly loud and distracting. I was in the immediate front row and the secondhand embarrassment almost led my introverted ass to ask him to give up on it already (while wishing he stops that second). However, he kept going on for another few seconds which felt like forever. Eventually stopped but ofc every time he tried grabbing again it was loud again.
Not sure if it's just me but I feel like this is pretty basic etiquette that we should know as adults/college students.