unwanted themes generated by my studio projects

This is the second project in which I experience the following problem :

I'm having troubles with the fact that my studio projects are automatically generating UI themes. The problem is that those themes make my DM default them completely unstable : no CSS themes at all, etc...
The first time I encountered this was following a change in the branding part of Studio, but now I'm facing the same problem with "projet aocdtf", despite the fact i didn't touch the branding part.
I know I can manually remove the theme folder if I "unzip" the generated jar, but that would not be a unconvenient solution.
No logs are showing up in the console.
Attached is a sample jar containing unwanted theme-related files.