code: function cssNameFromFilename( name ) {
  	if ( name ) {
  		const [ cssChunkFilename, chunkQueryString ] = name.split( '?', 2 );
  		return cssChunkFilename.replace(
  			/\.js$/i,
  			'.css' + ( chunkQueryString ? `?${ chunkQueryString }` : '' )
  		);
  	}
  }
docs: Transform webpack output.filename and output.chunkFilename to CSS variants
  
  @param {(string|undefined)} name filename, chunkFilename or undefined
  @return {(string|undefined)}     Transformed name or undefined