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So, I guess the answer could be the musical version of Li'l Abner.


There was an earlier version of LI'L ABNER in the '40's.

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If we're counting the comic strip FLASH GORDON (good call there, btw), then I guess technically we'd have to include popular comic strip character TARZAN THE APE MAN,


If you count comic strips then you can find short films/cartoons of various comic characters in the silent era. Maybe best to stick with live action versions of comics.