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Dexters Laboratory had the Justice Friends and one of them would always watch TV Puppet Pals which was about one character , though more yellow than orange, getting bonked on the head.
According to the page The Public Domain Channel, Fleischer and Terrytoons cartoons are often used for this purpose
Edited by mla
There was a Pinky And The Brain episode that featured a Show Within a Show called "Meany and Treacle" (parody of Beany and Cecil), and Meany was always bonking Treacle on the head.
My husband is trying to figure out what the cartoon is where, too often, in the background is another show or scene playing on T Vs. The scene always playing is an orange character "bonking" another character on the head. I believe he said the orange character would trick the other character each time. Again, this is going on on T Vs in the background of the real show.