Because of a decision made late in the editing process for James Woods' TV series 'Shark', the color of the shirt he was wearing switched from purple to black and back again to purple. Apparently there was no time delay between the scenes to indicate that he had changed his wardrobe several times over; it was supposed to be that each scene followed the previous one closely in the show's timeline.
The producer has stated that the error happened because he decided to go with a different scene (already filmed) in which to end the show, something more emotional involving Woods' character and his daughter. But there had been no prior indication that script continuity would even be needed for that scene because it wasn't even planned to be used at that time.
That's fine as far as a Trueniverse splainin goes, but what about in Toobworld? How come Sebastian Stark and his daughter Julie never noticed the color change? And what caused it?
Ever see those fashion commercials in which models will be walking along and their clothing instantly changes into something else and they seem to take it in stride? There's a car commercial out there now that has the same effect happen to a guy as he drives his new vehicle.
They don't even notice the change is happening.
Now, these occur in blipverts, but commericals are a part of Toobworld. So those models should have noticed the effect just like Stark, and yet for the most part it goes unnoticed.
I think the answer lies in magic.
There could be sudden overlapping breaches in the dimensional veil which separates TV dimensions, causing a TV character to be momentarily replaced by his doppelganger from another world. (This was the plotline for an episode of 'The Twilight Zone' - "Mirror Image".)
But more likely there's just some bored warlock out there who enjoys magically futzing about with mortal fashion, and making sure the "victims" don't even notice it (someone on the order of Uncle Arthur from 'Bewitched', perhaps).