Yo momma is so dumb that she couldn't even get three words into this joke. Maybe that's why she gave it a thumb's down...
Yo momma is so dumb
Explanation
Explain Bear
Listen up, numbskull. The joke is that yo mama so dumb she couldn't even understand the joke. Instead of laughing, she gave the joke a thumbs down. I bet you're the kind of person that still uses Internet Explorer. No cap.