openapi3 (v0.51.0): duplicate-type-name error when sharing type across routes w/multipart-form-data

[trrwilson]

[TypeSpec playground link to repro]

Using a custom type (tested: both model and enum) in a route that sets its content-type header to multipart/form-data appears to jealously guard against any other route using that type -- an attempt to do so results in

error @typespec/openapi/duplicate-type-name: Duplicate type name: 'MyModel'. Check @friendlyName decorators and overlap with types in TypeSpec or service namespace.

Omitting overridden use of content-type or setting to another value like text/plain or application/octet-stream doesn't encounter the issue, so it appears unique to multipart/form-data.

  @get listMyThings(input: MyRequestModel): string;
  @post uploadMyThings(
    // OK if next line commented out or using another type like text/plain
    @header contentType: "multipart/form-data";
    input: MyRequestModel): string;

Thanks!

[timotheeguerin]

This to be some issue with implicit body with the repro(if you add @body for the input everything is working fine, but might not be limited to that