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## 0.64.21

**`(feat):`** Introduce `x-fern-discriminated` extension to configure oneOf union behavior in OpenAPI specs.

```yaml
# Example usage in OpenAPI schema
oneOf:
  - $ref: '#/components/schemas/Circle'
  - $ref: '#/components/schemas/Square'
x-fern-discriminated: false  # Treat as undiscriminated union
```

When `x-fern-discriminated` is set to `false`, the oneOf will be treated as an undiscriminated union instead of a discriminated union.

## 0.64.20

**`(fix):`** Remove 'fern-check' error for global header examples included with 'x-fern-examples'

## 0.64.19

**`(fix):`** Pin Windows to legacy preview mode.

## 0.64.18

**`(fix):`**