Topic on Extension talk:WikiEditor

Using MW 1.35.0 and WikiEditor 0.5.3 You can try this out at: https://www.istaria-lexica.de/index.php?title=User:Elteria_Shadowhand/sandbox&action=edit

If I have a text, maybe 4000 characters or more, I cannot paste it into the editor. Sadly, google did not give me any hints about what is wrong. I assume it is some kind of spam protection?

Any ideas?

Thanks,

 Dominik