This error occurs when the compiler refers to a CSS rule that its stored results for a module do not contain. It can follow an incremental update in the development server or the editor.
How to report
Open an issue with the error message and:
- The source file and your stylesheet
- Whether the error appeared after a reload or an edit, and whether a clean build also fails
- The steps that reproduce it, if a clean build succeeds
- The version of the Stillwind packages