Special character is removed from property name in generated Typescript interface

When using the following schema:

"schemas": {
      "fooDto": {
        "required": ["$type"],
        "type": "object",
        "properties": {
          "$type": {
            "type": "string"
          }
        },
        "discriminator": {
          "propertyName": "$type",
          "mapping": {
            "SomeDto": "#/components/schemas/someDto",
            "OtherDto": "#/components/schemas/otherDto",
          }
        }
      },

The interface that gets created is:

export interface ContentDto { 
    type: string;
}

In this interface the dollar sign is removed.

Is there a way to prevent this from happening?

Start with the supplied OpenAPI schema and the TypeScript interface-generation entry point; compare the $type property in the input with the emitted type property. Confirm the expected preserved property name and add or run a focused regression case for this schema, then verify that generated output keeps $type.