Can not submit a new version

When press Add Version button (after validation), The submitted file is empty. message is shown and can not submit a new version.

Found why.
Firefox 46 unable to add new version of unlisted, multi-platform Valence add-on · Issue #1503 · mozilla/addons-server

After much investigation, it seems the FormData behavior changed from FF 46: 1241171 - FormData should not force 'blob' as filename.