I have a couple of RTC users who are unable to open Plans in the web UI. They get the following errors:

Firefox:
Type error: other is null
And you get this in the error console:
Error: syntax error
Source File: https://host name removed :9443/jazz/_theming/allThemeJS/_current
Line: 1, Column: 1
Source Code:
Unable to initialize the theming service

IE:
"Type error: 'declaredClass' is null or not an object.

This started a couple of days ago. They have not yet verified for me if this is also occurring in the RTC client. Any ideas?