https://pastebin.com/gK37BPds

So I've created a custombook. I've placed the book in xml format outside of my resources folder. When I get into the game, I see 2 guidebooks. One is the demo book that comes with the mod. The other is a blank named guidebook despite giving the book a title in the xml file and cover graphic that has been placed in the resources/texture file. It's the same texture I used for this mod back in 1.12 so I know it works.

When I open the blank book without a name, I see an empty book and the game goes back to the "Saving world" screen. I am then kicked out with that error.

Thanks for reporting, I'll take a look as soon as I can.

Would it be possible to send me a copy of the book causing the crash? It seems to be a corner case of my word wrapping logic, and it's hard to reproduce.

I put it in a text file since I can't upload xml files here. All I did was take the template, change the book name and the texture for the book. I was then going to copy over some of my 1.12 parts of my guidebook after I saw it loading into the game because a lot of it is the same.

cyla.txt

I have been trying to reproduce your issue with the xml file you showed, and I can't. I also can't find any reason for why it would recurse infinitely, since I have checks in place. It's very strange. Only thing I can think of would be some very strange corner case in the logic, which only happens for very specific window size + gui scale combinations.