Darths and Droids always has text below the comics, but I wouldn’t call it footnotes: It’s more like a short essay, or blog post, of tips on how to run an RPG. Or how not to: Some of it is unabashedly bad advice.
They also now have commentary by one or two fans who are reading the comics, but who have not watched the movies they’re based on. Those often include speculation on what the movies were actually doing.
National Lampoon had an X-men spoof (X-Women) where the lady superheroes sat around and griped about how bloated they were and what time of the month it was and the last panel had a footnote saying Be sure to watch for your next monthly issue.
Similarly, NatLamp did The Amazing Squirrel Man (Spider Man spoof) where he cornered the bad guy — who was carrying a vial of deadly cancer — and told him to drop that vial! Then, the footnote: Next: Everyone gets deadly cancer!
Wai wai wai wai waaaaaaaaaaiiiiiiiiiit . . .
Lower Decks has a comic too??!!?? Whereabouts may one find this aforementioned literature?
Tripler
My bedtime reading has now irreversibly taken a new course.
Well, there is the first, 3-issue series
And the new, ongoing series
And the choose your own adventure comic
Aren’t these just a version of “Editor’s Notes?”
Incredibly common in comics.
I haven’t seen them anywhere other than the two titles I mentioned. Can you give other examples? It is a very specific thing I’m looking for—joke comments made below the bottom panel of nearly every page of the comic. No other type of editorial marks are on-topic.
comic book writer John Broome got so taken with his concept of “Cribi” (virtually indestructible alien abstract art that is all that remains of a long-dead race) that he put a three-panel footnote explaining the concept into his story “Menace of the Reverse Flash” (the story that introduced Professor Zoom/Reverse Flash/ Eobard Thawn) in the September 1963 #139 issue of The Flash
Yeah, a clever way to say “see, you should be buying ALL the issues of all the titles!”
…
And of course gotta mention Masamune Shirow’s Ghost in the Shell that featured footnotes AND endnotes.
Herge dropped a footnote to this effect in the Tintin comic Explorers on the Moon, when Thompson and Thomson started suffering effects of pills they’d ingested several issues earlier.
SMBC, too.
Whenever Mr. Walker was mentioned in Phantom strips there would be a note at the bottom of the frame saying *for the ghost who walks,
Likewise, when he was speaking with his friends, the Bandar people, there would be a footnote saying “In the Bandar tongue.”
Remember the old Sugar and Spike comics? Sheldon Mayer would sometimes include footnotes to comment on what was happening in the story. One I remember particularly well came from an adventure set in Latin America:
Fershlugginger: A word Tortillans use all the time. They don’t know what it means, but they learned it from reading MAD Magazine.
None of us non-Tortillans know what it means either. IIRC it was spelled “Furshlugginer”.
Which was also known to use footnotes. (One from their film spoof “Rambull III,” in a panel where the title character cauterizes his wound with gunpowder: “CAUTION! Rambull is a trained professional! Don’t try this at home!”)
Correction noted! Thank you! 
They used it in reference to a mountain that was difficult to climb and/or descend. I was 11 or 12 at the time, and I could tell from context that it was pejorative.
And explanations about his Good Mark and Bad Mark.
I remember those from back in the 1960s, when DC had some children’s comics among its offerings. Another children’s title I remember was “The Three Mouseketeers,” and I believe Sheldon Mayer had a hand in that too.
DC wasn’t always superheroes. In addition to the above comics for children, they also published comic versions of Jerry Lewis and Bob Hope. I’ve never forgotten the name of Bob’s hapless assistant: Tadwallader Jutefruice. And if I recall correctly, DC also had some romance comics too.
S&S had a section where kids sent in their designs for clothing you could cut out of the comic and put on paper dolls of the two babies. One of mine got printed in an issue when I was in fifth or sixth grade.
In one letter from a reader, Mayer was asked how to get started as a comic book artist, and what he considered his greatest achievement. He wrote a long reply about his early years in the business and how he discovered Carmine Infantino, who went on to become an artist and editor at DC during the Silver Age of the '50s and '60s.