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## 0.42.1

**`(fix):`** Make sure to check for optionality when parsing stdout and stderr in CLI. This
removes the error: `Cannot read properties of undefined (reading 'includes')`.

## 0.42.0

**`(fix):`** If you merge multiple OpenAPI specs with namespaces, `fern check` will no longer
complain about duplicate schema names across namespaces.
In the example below, both OpenAPI specs can have duplicative schema names and
that is okay.

```yml
api:
  specs:
    - openapi: openapi-bar.yml
      namespace: bar
    - openapi: openapi-foo.yml
      namespace: foo
```

## 0.41.16

**`(fix):`** Previously the OpenAPI converter would incorrectly mark
the values of `additionalProperties` as optional. Now, we have
introduced a feature flag to turn this behavior off.

The feature flag can be configured in generators.yml:

```yml
api:
  specs:
    - openapi: /path/to/openapi
      settings:
        optional-additional-properties: false
```

## 0.41.15

**`(internal):`** Performance improvements for stringifiying large Intermediate Representations. If
you have a large OpenAPI spec or Fern Definition, this can potentially shave off
minutes from `fern generate`.