> For clean Markdown content of this page, append .md to this URL. For the complete documentation index, see https://buildwithfern.com/learn/llms.txt. ## 1.16.5 **`(fix):`** Fix duplicate array types in undiscriminated union properties. Previously, nested unions containing different array types (e.g., `array` and `array`) would generate duplicate array annotations in PHP union types (array|array|null). The fix implements recursive union flattening with proper deduplication during type generation.