"Bethesda's Bug" refers to a flaw in design that cannot be explicitly defined as intentional or accidental, coined by Joesph Anderson in an analysis of the game Fallout 4 on Youtube.

You might have experienced a feeling where you forget you are watching a movie. You might forget you are reading a book and the world it creates becomes this oasis in your imagination. The best works of fiction feel like extensions of reality with characters that walk off the pages.
Bethesda's Bug breaks a player's immersion and at worse disconnects someone from a world they were enjoying and makes them question that world the developers have built. It makes that world feel small and reveals that it was not fully realized and might make you want to put an otherwise good game down.

"Bethesda" is a studio that develops videogames and a "bug" refers to a behavior a creator may not have intended (almost always referring to videogames or software). "Bethesda's Bug" is a transmogrification of the "Schrödinger's Cat" thought experiment.

Anderson, J. "Fallout 4 Analysis". 28 November 2015. Youtube.

What constitutes a "Bethesda's Bug" is pretty nebulous. Any example I can think of that actually qualifies is far too intensive for the purposes of this definition.
I suggest* you watch Joeseph Anderson's Fallout 4 Analysis video on Youtube if you want an example in context. It's a long video but it is worth the watch if you like excessively critical analysis. 25 minutes in he mentions Bethesda's Bug.

*He will spoil the game so if you have any intention of playing Fallout 4 I suggest you go in blind and form your own opinions before exposing yourself to a review.*

Bethesda's Bug by iamaniceguyonceyougettoknowme October 14, 2019

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I really like that girl named bethlehem!

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Person 1: Doesn’t he go to Bethlehem Catholic High School?
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