protected function filterItemsForNotPossibleMinifiedAndPossibleMinifiedItems ($items) {
		$itemsToRenderMinimized = [];
		$itemsToRenderSeparately = []; // some configurations is not possible to render together and minimized
		// go for every item to complete existing combinations in attributes
		foreach ($items as & $item) {
			$itemArr = array_merge((array) $item, []);
			unset($itemArr['path']);
			if (isset($itemArr['render'])) unset($itemArr['render']);
			if (isset($itemArr['external'])) unset($itemArr['external']);
			$renderArrayKey = md5(json_encode($itemArr));
			if ($itemArr['doNotMinify']) {
				if (isset($itemsToRenderSeparately[$renderArrayKey])) {
					$itemsToRenderSeparately[$renderArrayKey][] = $item;
				} else {
					$itemsToRenderSeparately[$renderArrayKey] = [$item];
				}
			} else {
				if (isset($itemsToRenderMinimized[$renderArrayKey])) {
					$itemsToRenderMinimized[$renderArrayKey][] = $item;
				} else {
					$itemsToRenderMinimized[$renderArrayKey] = [$item];
				}
			}
		}
		return [
			$itemsToRenderMinimized,
			$itemsToRenderSeparately,
		];
	}