popNewAssets = assets => {
			let newAssets;
			for (const file of Object.keys(assets)) {
				if (savedAssets.has(file)) continue;
				if (newAssets === undefined) {
					newAssets = Object.create(null);
				}
				newAssets[file] = assets[file];
				savedAssets.add(file);
			}
			return newAssets;
		}
@param {CompilationAssets} assets assets
@returns {CompilationAssets} new assets