i have seen all of these multiple times and i will provide examples if asked

• suicidal depression as comedy
• when a character is canonically evil and also german and/or involved in the military somehow... and the fan content portrays them as a nazi (if you do this you WILL be going to hell)
• when more than like 2 people are making the same facial expression in an image
• when there's a character nobody (in-universe) likes and then half the jokes involving the character are that nobody likes them