If I try to open CSS files with the Eclipse CSS editor I get the error:
"Unsupported Content Type in editor. To associate file extension with a supported content type, please see Content Types Preferences Page."
- Check "Do not show this message again" on the dialog above.
- Remove Aptana Web nature from the project. The effect might be that you may not me able to use Aptana Studio editors in full.
- Do not use WST editors
See https://bugs.eclipse.org/bugs/show_bug.cgi?id=268635 for the root cause of this bug.