Error with kissmanga.com

[Yoposoc]

I'm getting this error on the kissmanga.com viewer.
I'm actually not sure what error this is causing/caused by, because it seems like I can use the userscript just fine after pressing ok.

[Yoposoc]

I still have this problem by the way. And I've noticed that after this, the userscript can't do any auto-shrink height or width.

[ahegaofish]

use mangadex XD