Rage

What the picture shows

A small red jagged burst or starburst shape made of curved lines sits in the upper right of an otherwise blank white square, resembling a cartoon anger or impact symbol. Chatters would likely use it to signal frustration, irritation, or a sudden spike of rage in response to something in chat.

No measured meaning yet. Used 8 times in 3 channels this month; one is written once chat gives enough evidence.