I'm using CkEditor in a GWT integration. This worked well until I just tried to update to the latest version 4.2 from version 4.0.1. I tracked this problem down to the isArray method in the tools.js file. The instanceof method works if you receive data from the same frame as where you are using the editor. When you send an object to an another frame, the instanceof Array method will no longer work. More details on this problem, and how to solve it is described here:
http://perfectionkills.com/instanceof-considered-harmful-or-how-to-write-a-robust-isarray/
I should also probably
I should also probably mention that GWT always loads all code through an iframe, which makes the current editor incompatible with a GWT environment.
Ticket created in Trac:
Ticket created in Trac:
https://dev.ckeditor.com/ticket/10666