When Peter as Han Solo is revealed in carbonite as Jabba's "favourite decoration", he's looking over his left shoulder while mooning. But when he was encased in carbonite during Something, Something, Something, Dark Side (2009) he was looking back over his right shoulder.
When Peter/Han was tied up to be roasted by the Ewoks, they were starting the fire under him, and in the next shot of him the fire is not there at all.
When the Rebels are fighting around the Death Star, one view shows the unfinished part of the Death Star to the right of the Starkiller, yet another shot shows the unfinished part to the left.
Before Chris dressed as a Jedi breaks Stewies neck while dressed as Darth Vader, the spaceship ramp behind him is at a very steep angle. The next scene when Chris walks up the ramp with Stewie the angle is now less steep than before.
When everyone races off on speeder bikes, a third Stormtrooper takes Pee-Wee Herman's bike from Pee-wee's Big Adventure (1985), to make a joke reference to the plot of that movie, but none of the Stormtroopers are riding that bike after that. Two appear later on red bikes, but these are of the same simple design as the others.
The giant Rush Limbaugh monster says, "No tax-dodging Jedis in my pit!"; the word "Jedi" is both a singular and plural noun, so no "s" is added to the word to pluralize it.