Visible crew/equipment: The metal wires and rods that were used to build the giant spider web are visible through the web structure. (01:14:00)
Visible crew/equipment: When Jeremitt and Catarine are looking for Cindel and Mace, the electric cable used to power the device they wear to see if each other family member is alive can be seen dangling from their wrists.
Visible crew/equipment: When Wicket's parent is hang gliding, the actor who plays him can be seen under the Ewok suit. (00:06:05)
Visible crew/equipment: When the spider is attacking one of the Ewoks and one of the other Ewoks uses a magic spell on the spider, wires can be seen on the spider. (01:16:25)
Suggested correction: This isn't a mistake. That's him, under the water in the same pose he was in before he touched the water.
After watching the scene, the mistake is valid. When he's underwater, he's not in the same "pose." That would require him to be upside down and squatting. But that's not the pose we see him in.
Bishop73
We see Mace semi-kneeling and reaching out to touch the water when he vanishes, but his upside-down reflection is still in the exact same calm position even when he's gone, and in the next shot we see Mace under the water right-side up, with his arms reaching up to the surface. This is a valid mistake, the suggested correction is not right.
Super Grover