Doug is Quailman / Doug Out in Left Field - S1-E12
Other mistake: Doug is Quailman: When Doug, as Quailman, gives everyone's brains back and they start cheering, the computer and boy behind Skeeter are layered over him for one frame. (00:09:24)
Doug is Quailman / Doug Out in Left Field - S1-E12
Other mistake: Doug Out In Left Field: When the kids are carrying Patti at the end, there is a boy behind Doug whose blue shorts keep flashing green, and his light green hair keeps flashing dark green. In the next shot, his hair stays dark green. (00:22:21)