Merge Theme from several Jars


we are currently plan to create an application that will consist of several sub applications. The sub applications will be included as Jars into the main application, but developed completely independent.

There would be a need of those sub-application developers to include their own images and css into their application.

Is there a possibility to merge their theme (resources) stuff together with the “main” theme stuff located inside the core application? Maven is used to build the project.

As far as I tried it out it is possible to include a theme jar /like vaadin-themes), but I did currently not find a way to merge multiple theme parts from different jars.

Thank you!

EDIT: As far as I can see (as the theme is compiled to the styles.css file) this is not possible currently for the css styles (one would have to extract the styles.css files out of the single jars and merge them together), for the image resources it works by simply having them at the correct path.

I am currently evaluating if may be it is possible to add the other css files under a new name inside the head section of the html page using a Bootstrap listener.

Unfortunately this really introduces limitiations for this kind of project.