An example of a warning generated by the error console is as follows:
Resource interpreted as other but transferred with MIME type text/css.
Steps to reproduce this are as follows;
1. Navigate to any webpage.
2. Using the Develop menu item, choose Show Error Console.
3. Reload the page using Command + R.
4. Observe the webpage elements appear in the Error Console.
I do not believe this is a server issue, as it occurs on any webpage, and the problem does not seem to exist in Safari or Firefox.
Confirmed with r39509, using http://www.google.ru. But some of subresources are OK semi-randomly, which makes me suspect that recent purging/caching changes may be related.
Inspector probably needs so know about the cache validation mechanism.
*** This bug has been marked as a duplicate of 22994 ***