What Would Lucifer Do? - S3-E4
Other mistake: When Lucifer grabs Amenidiel's phone and is supposedly typing on it, he's holding it upside down. (00:06:25)
The Angel of San Bernardino - S3-E20
Other mistake: Lucifer's obsession with Bones is highlighted here when he confronts someone as a killer only to realise it's because he's an actor who played a killer in the Bones episode Intern in the Incinerator (a role Scott Rinker did play in real life). Kevin Alejandro (Dan) and Aimee Garcia (Ella) also played roles in Bones, which Lucifer never comments on. In fact so did Jeremiah Birkett (Lee Garner, "Mr. Said Out Bitch").
Answer: Boo Normal and Once Upon a Time were going to be part of season 4, then the show got cancelled (before being picked up elsewhere). As such they were added on to the end of season three as "bonus" episodes, hence the continuity being off. But not really a mistake, just a quirk of broadcasting. Boo Normal was originally going to be between the episodes "High School Poppycock" and "Infernal Guinea Pig" in season 3 before being slated for season 4, presumably because aside from the point you've raised, it was fairly flexible, continuity-wise.
Jon Sandys ★