Bugs Bunny's eyelashes briefly disappear and reappear while covering his bra with his left hand and trying to use his bra to tie up Porky and his hunting dog.
In Tales From The Vienna Woods, when Porky makes his initial appearance, he is hunting with a blunderbuss (a firearm with a funnel-shaped muzzle, and which shoots a group of assorted multiple small projectiles like small lead balls or buckshot, rather than a bullet or single large ball like a pistol or musket). But after Porky and his dog confront Bugs Bunny in the bush and jump out, Porky reappears with a conventional straight-barrel rifle.
The exact same branch is shown on both occasions when Mama Goose holds it up for her brood to pass underneath, even though the surrounding scenery is different.