When I was writing in a writable book that I had already previously edited the cursor appears ahead of where I'm writing.

It only affects pages with a large amount of text and after messing around with it for a bit I found out that it specifically affects paragraphs where the player writes enough text for it to wrap around to a new line. The first line of the book seems to be okay but on the second line and any lines after that, the displacement of the cursor gets worse.

It seems to be incremental too, on the second line it's off by one character, third line it's off by two characters, fourth line it's off by three and so on.