# Changes to CSS Parser Algorithms ### 4.0.1 _September 25, 2026_ - Improve performance - Throw when the nesting depth of functions and simple blocks exceeds the maximum - Updated [`@csstools/css-tokenizer`](https://github.com/csstools/postcss-plugins/tree/main/packages/css-tokenizer) to [`4.0.1`](https://github.com/csstools/postcss-plugins/tree/main/packages/css-tokenizer/CHANGELOG.md#401) (patch) - Updated [`@csstools/css-tokenizer`](https://github.com/csstools/postcss-plugins/tree/main/packages/css-tokenizer) to [`4.0.2`](https://github.com/csstools/postcss-plugins/tree/main/packages/css-tokenizer/CHANGELOG.md#402) (patch) [Full CHANGELOG](https://github.com/csstools/postcss-plugins/tree/main/packages/css-parser-algorithms/CHANGELOG.md)