Disable text features?

[betsybugaboo]

I'm not good at coding, so I just want to know, how do I comment out/disable some of the text formatting stuff? Specifically the line break editor. There's plenty of older fic that has weirder typography that it automatically reads as 'intended to be line breaks' and replaces it with a

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even when it isn't, cutting off text. I want to be able to turn it off.