Other mistake: When Rex shakes the table causing the baby monitor to fall, the batteries fall out and we see the open battery compartment with markings for positive (+) and negative (-), and space for two AA batteries. Woody jumps off the bed and places the two batteries inside the compartment, but before he closes the compartment note the position of the battery closest to the top of the monitor. The positive side is actually where the negative side should be so the monitor should not work, but the monitor turns on just in time to hear the soldier's warning. (00:13:15)
Other mistake: After the magnet grabs Slink during the incinerator scene, all the toys grab metal objects to avoid getting torn up. Afterward, they all let go of their metal objects to drop down. However, Slink also drops down despite not holding on to anything because he is made of metal.
Suggested correction: Or, the other toys helped him down.
Other mistake: When Elastigirl is chasing the high-speed train, as she is in the middle of making her second final jump to reach the train, if one were to look closely, the train actually drives right past her before she lands. (00:31:40)
Other mistake: When Skinner calls his lawyer he never dials the phone.
Other mistake: When Hamm turns off the TV at the beginning, there's no reflection of him, Rex who is beside him, or the remote. (00:06:58)
Other mistake: After the first race, in the scene where Lightning is rushing out on the stage thinking he is the winner, loads of confetti is shot out when the King and Chick Hicks gets onto the stage. The confetti is then falling down, but not a single flake hits any of the cars. However, in the following shots, you can see plenty of it on the stage underneath the cars, even though they haven't moved.
Other mistake: Near the end of the film, when the identity of 0001 of the CDA is revealed, number 0112 is shown both standing next to 0001 as Roz enters the room and behind Sully and Mike on the opposite side of the room. (01:16:45)
Other mistake: On the ship, Wall-E leaves dirtmarks everywhere, except when he's hiding behind an EVA pod. (00:37:20)
Other mistake: Towards the beginning of the film, the teacher counts 19 students then says one is missing, implying there are 20 (including Mike) However, Mike ends up being paired with the teacher, despite there being an even number of students and therefore everyone should have a partner.
Other mistake: Near the end of the film when Jack-Jack is manifesting various abilities, his first display is of the human-torch-type of superpower. This would have burned away all of his clothing, yet (for obvious reasons) his diaper remains intact. This is particularly apparent as designer Edna Mode's costume for Jack-Jack was earlier shown as fire-resistant, but he was not dressed in his outfit during this scene. (01:44:15)
Suggested correction: This is definitely intentional, not an error. We see Jack-Jack use his fire powers without burning his diaper in Incredibles 2. Having fire powers without burning clothes is just a retcon.
Other mistake: When Miguel is singing "Un poco loco" on stage, he goes out of range of the mic, but his voice is amplified.
Other mistake: In London, the red telephone boxes seen are human-sized, so it is impossible for them to be big enough for the cars to even get into.
Other mistake: The Spanish version has all the titles and signs changed to Spanish text as we can see when Carl opens the photo album. However, a side angle shows the letters 'O' and 'D' revealing it's the original English text, "Things To do."
Other mistake: When Riley and her parents arrive at their new home in San Francisco, several pieces of mail are sticking out of the mail slot in the door. A letter carrier would not deliver mail to a vacant house, let alone not push it all the way through the slot.