IllegalArgumentException when compiling scss on the fly in spring boot proj


I created a spring boot 1.4.2 vaadin 7.7.5 project with spring initializer. Works fine. Debug mode is enabled.

Then I added a custom theme, which for testing just contains a simple color change.

I start the application via CLI:

java -jar target/application-0.0.1-SNAPSHOT.jar Now when trying to compile the scss on the fly I first get some “Base-level rule contains the parent-selector-referencing character” warnings. These I also get when compile via maven, so it’s annoying but should not be critical I think, right?

But after the on the fly compile I get this error causing no css at all to be available in the application:

SEVERE: Servlet.service() for servlet [springVaadinServlet] in context with path threw exception java.lang.IllegalArgumentException: name When I start the application via mvn spring-boot:run the error does not happen.

Any ideas what causes this error and how to avoid?

Thanks for help,