The Kernel does not match the mimes version
I have seen several cases where a message is displayed when accessing WEBGUI, Personas or any ITS-based service:
There are cases where, upon investigation (using Fiddler, HttpWatch), the rendering version from the kernel did not match the one from the MIMEs. In one example, looking inside the trace, the version found was 10.30.0.231760.0, but the expected version was 10.30.1.236206.0. Thus, the warning was expected.
The recommendations to resolve the issue can be found in KBA 2234414.
One comment, In our case, only certain users experienced the issue and not everyone. Clearing the browser cache didn't seem to help. We didn't see any entries in the Web dispatcher cache folder either,I believe SAP Web Dispatcher comes with caching turned off default too.
Have a test with another web browser. Does the behavior persists? I would record a Fiddler trace and see from where the mimes are coming, and compare the version available in the server. I also would perform the steps from note 1575271 in all app servers.