Tiny MCE Pop Up shows blank in Portal 7.3 EHP1

Hello Experts,

We are facing an issue in tiny MCE Editor post upgrade to 7.3 EHP1. We have upgraded our portal from 7.0 to 7.3 EHP1. Post upgrade, the tiny MCE editor, shows pop up windows as blank.

We referred some of the threads, for setting document.domain ="Domain name" for cross subdomain in tiny_mce_popup.js file. However, that did not work.

We also tried to maintain FQDN in the same file and deploy. We did the same for other .js files and maintained document.domain ="FQDN name". That did not work either.

Has anyone faced this issue and was able to resolve it?

Any inputs in this regards will be helpful.

We need to find a solution for this soon.

Thanks,
Prasanna