That would be a daft thing to do as it seems so tied to WB but:

it is worth noting that the original Looney Tunes animated shorts, which ran from 1930 through 1969

A lot of these are public domain already because their copyright wasn’t renewed. For those under copyright the public domain wall is approaching:

The earliest currently copyrighted Warner Bros. cartoon, “Ride Him, Bosko!”, is set to enter the public domain in 2028.

So, while some later cartoons are PD, some first appearances of classic characters (albeit often in unnamed and prototype form) aren’t but the wall approaches:

• Porky Pig - first appeared in “I Haven’t Got a Hat” (1935) - PD in 2031
• Daffy Duck - first appeared in “Porky’s Duck Hunt” (1937) - PD in 2033
• Elmer Fudd - first appeared in “Little Red Walking Hood” (1937) - PD in 2033
• Bugs Bunny - first appeared in “Porky’s Hare Hunt” (1938) - PD in 2034