Obscure word for a transcription error

Factual Questions
1

A while ago, I remember reading of an incredibly obscure word that meant something like: “a phrase or sentence that is repeated in a text as a result faithful copying of an earlier text, which earlier text mistakenly repeated that phrase or sentence when transcribed from an even earlier text”.

I seem to remember the word was useful when studying the origin of a particular book or edition (such as very old bibles for example) because it allowed researchers to figure out which book was copied from what.

Can anyone enlighten me?

2

Can’t think of a single word, but this sounds like “scribal glosses”. See, for instance, here.

3

The original mistake of repeating a word or passage is called “dittography” and a passage so repeated is called a “dittograph.” I don’t know of a word that means the faithful copying of a dittograph.