When Festus introduces Mayblossom to Lon before they fight, Lon is wearing his
gunbelt. During the fight, it disappears.
When Festus is seen at the bottom of Doc's stairs, and when Mayblossom comes down the stairs, there is an advertising poster for Hill's Mercantile to the left of Doc's sign. A few minutes later, when Mayblossom rides by Doc's sign, the mercantile sign is gone.
When Festus, Mayblosson and Feeder are talking in Mayblossom's house, the door keeps changing from fully closed to partly open.