re: #29 Love-Child of Cassandra and Sisyphus

But if one is using a no-longer protected image, how can that also be still protected by trademark?

Quoth the WIki:

On January 1, 2009, 70 years since the death of his creator, Segar’s comic strips (though not the various films, TV shows, theme music, and other media based on them) became public domain[61] in most countries, but remain under copyright in the United States. Because Segar was an employee of King Features Syndicate when he created the Thimble Theatre strip, it is treated as a work for hire under U.S. copyright law. Works for hire are protected for 95 years from publication or 120 years from creation, whichever is shorter.[62] As of 2024, Thimble Theatre comic strips from 1919 through 1928 have entered the public domain, concluding seventeen days before Popeye’s first appearance. Even after the strips enter the public domain, trademarks regarding Popeye remain with King Features, as trademarks do not expire unless they cease to be used, and King Features has used the trademark continuously since the character’s debut.

en.wikipedia.org