This happens because of same-origin security policy of browsers used to prevent XSS attacks, it doesn't seem related to the diagram itself. The error would happen if any script loaded through the IFRAME tries to access main page objects or vice-versa. You will just need to change the IFRAME's source to use the same port as the main page (e.g. 41110 instead of 16405 shown in the stack trace). For more information on same-origin policy see http://stackoverflow.com/questions/25098021/securityerror-blocked-a-frame-with-o...

edit: Only suspicious thing I can see in collapse method (from top of stack trace) is a reference to MindFusion.Collections, which is defined in separate common.js file. So if you need to keep the iframe on a different site, maybe check if the application loads common.js from top-level page and diagramming.js from iframe.

Regards,
Slavcho
Mindfusion

We have a bug-fix related to that property listed in 2.6 releases notes, please check if latest version fixes the exception for you -
http://mindfusion.eu/Forum/YaBB.pl?num=1464603622

The cross-domain error might be happening if some exception-handling scripts of yours load from a different port, so you might still want to look into that even if latest version fixes the original exception.

Regards,
Slavcho
Mindfusion

i think those two lines should fix your iframe issue:

    <meta http-equiv="X-Frame-Options" content="allow" />
    <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE10" />

 

just in case  you are trying to implement data communication between parent and iframe page just give up