code: public static InputStream getResource2(String uri) {
      try {
        // If -Dwebdev=1 is set in VM args, we're in front end dev mode, so skip the class loader.
        // This is to allow the front end scripts/styles/templates to be loaded from the build
        //  directory during development.
  
        // Try all registered locations
        for( File f : RESOURCE_FILES ) {
          File f2 = new File(f,uri);
          if( f2.exists() )
            return new FileInputStream(f2);
        }
  
        // Fall through to jar file mode.
        ClassLoader cl = ClassLoader.getSystemClassLoader();
        InputStream is = loadResource(uri, cl);
        if (is == null && (cl=Thread.currentThread().getContextClassLoader())!=null) {
          is = loadResource(uri, cl);
        }
        if (is == null && (cl=JarHash.class.getClassLoader())!=null) {
          is = loadResource(uri, cl);
        }
        if (is != null) return is;
  
      } catch (FileNotFoundException ignore) {}
  
      Log.warn("Resource not found: " + uri);
      return null;
    }
docs: from a possible local dev build.