Accidentally-Correct Writing: In "Desperada," the heroes knew they were under the Eiffel Tower while in the sewers due to signs mounted on the sewer walls. Parisian sewers do in fact have street signs in them due to the Parisian Sewer Museum being a tourist attraction located in the sewers.
"Glaciator" was supposed to be released but got scrapped and declared non-canon to the comic for being too short and irrelevant. What remains of it was posted on the author's Patreonin two parts. It was later reworked into a second Intermission for the middle of Season 4.
A bonus panel for "Glaciator" has Marinette crying into her pillow after hearing Chat Noir say he was in love with someone else when André the ice cream maker mistook him and Marigold as a couple. It wasn't released due to the author changing the dialogue so that Chat Noir instead said that he only sees Marigold as a friend.
Flip-Flop of God: The author explains that part of the reason Roger was willing to take Chloé's noise complaint seriously in "Captain Hardrock" was because her father gave him a promotion at the end of "Rogercop"; at the end of the episode, though, Officer Raincomprix informs Chloé that the mayor doesn't actually have the authority to fire him, which would imply that he doesn't have the authority to promote Roger either.
Master Fu doesn't try taking the Ladybug Miraculous from Chloé despite all her blatant misuse of it. The canon episode "Feast" revealed that Master Fu can have Wayzz follow and steal the Miraculous back from their users should he ever feel the need to do so.
In the comic, it's established that Tikki using Lucky Charm by herself creates way too many objects. The canon episode "Dearest Family" revealed that she would actually create one humongous object.
Near the end of "Zombizou" in the comic, Sabrina states that Mme. Bustier knew for years that Chloé's been cheating to get through school yet refused to do anything about it. It was drawn prior to (although not released until after) the canon Season 5 episode "Revelation," in which Mme. Bustier finally learns that Sabrina has been doing all of Chloé's schoolwork since grade school, having previously been unaware of it.
It wasn't until Season 5 of the show that Lila's hairstyle was revealed to be a wig, and it also turned out that she was pretending to be the daughter of multiple women, with it being uncertain what her real name even is. Since she had her redemption arc in the comic before Season 5 came out, it can be assumed that in this version, she only has one mother, Lila Rossi is her real name, and her hair isn't a wig. "Catalyst" incorporates some of these by having her mention that she lost a bet and was going to cut and donate her hair, while also revealing that her two other mothers are her stepmother and godmother. It's also explained that her other names from the show are her middle names here.
Shrug of God: After giving Nadja her cake in "Timebreaker," Marinette sees a bike nearby and ends up using it to get back to the fight. The author refuses to confirm or deny that the bike was Marinette's.
Trolling Creator: During "Queen Wasp", the author reblogged some art she'd previously drawn of Zoé using the Ladybug Miraculous, with the tags saying that she was bringing it up for no particular reason, implying that Zoé would use the earrings in this episode. The author eventually admitted that actually, Marigold was going to unify the Ladybug and Bee Miraculous, and that she had intentionally misled the readers by reblogging the art of Ladybug Zoé.
According to two of the tags to the part where Marinette reveals she had "mandatory gùn training with Maman," it would have been "bo staff training," but "that's Japanese."
"Glaciator" was worked on as an episode but later got removed from the comic schedule so that an adaptation of "Crocoduel" could be included instead. It was stated that the episode would no longer be canon to Scarlet Lady, since there wasn't too much that happened in it anyway. As the author had already completed all the pages for the episode before reaching that decision, she consulted her Patreon backers and decided to release it on her Patreon without a paywall so that followers can still see the episode while keeping it off her blog proper to avoid confusion about its canonicity. Eventually, as suggested by her Patreon backers, she decided to rework the episode into a second Intermission that takes place halfway through Season 4.
Originally, Chat Noir would refute André the ice cream maker's false assumption in "Glaciator" that the former and Marigold are a couple by stating that he's in love with someone else. This would then be followed by a bonus panel with Marinette crying into her pillow over this. However, the author felt that it would be Out of Character for Chat Noir to say that and thus instead just had him declare that Marigold is only his friend. The bonus panel was thus also cut.
Most of the other Miraculous originally weren't going to be included in the comic, but the author eventually decided to include all of them except the Rabbit Miraculous. She later said that if she'd known she would use all the others, she would have adapted "The Pharoah" later and had Bunnyx make an appearance then (this presumably would have been her only major appearance due to the author not wanting to involve time travel too much).
When asked if Chloé in this AU is gay, the author replied that she's "Power-Money-Fame-sexual" and would have pursued Kagami for this reason if the latter weren't friends with Marinette.
Marc has been confirmed to be nonbinary, as evidenced when they tell Marinette what their pronouns are in "Riposte."
Kagami is shown to have a hero crush on Marigold, as seen when she gets a Marigold-themed ice cream and when she grabs unto Marigold in "Ikari Gozen." According to the author, it's just a crush—Kagami isn't in love with her. "Frozer" later confirms that Kagami is a lesbian.
In "Glaciator," Alix makes a direct remark about being aromantic. The episode was cancelled at one point, but the author has brought it back as a second "Intermission," which makes it canon to the AU.
Write Who You Know: Alya's line in "Sapotis" about how Chris gets to stay up one hour later than the twins because he's one year older than them is based off the author's mother saying the same thing to her little sister.
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