The hardcoded https://github.com/cxong/cdogs-sdl/blob/d99a1999a19ae78ee28d9cfdea51c996a461b092/CMakeLists.txt#L156 breaks https://github.com/flathub/io.github.cxong.cdogs-sdl/issues/1. https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html