After upgrading from FlexDeploy versions 6.0.0.0, 6.0.0.1, 6.0.0.2, or 6.0.0.3, users will need to hard refresh their browser or they will see errors on the screen. The errors will look something like this:
The workaround is to press CTRL+F5 to refresh the page, or press F12 to go to developer mode and disable the cache.
This was caused by caching of the index.html file in versions 6.0.0.0-6.0.0.3. The issue is resolved in 6.0.04+ and 6.5.0.0+.
So, if you are on 6.0.0.0-6.0.0.3, you should disseminate this document or another of your design that indicates that a hard refresh is needed if you experience this sort of error.