git push option merge_request.assign=USER only works if USER is in the origin repo, not in the target repo.

I have 2 repositories:

• upstream
• downstream (forked from upstream).

If I push a branch to downstream with the following options:

git push downstream new-feature -o merge_request.create -o merge_request.assign=USER

The new merge request will NOT be assigned to USER unless USER is also a known user in downstream.

The UI can correctly assign the MR to USER.