I think it’s a “browsers don’t like it if a newly opened windows only purpose is to download a fail, when opened via target=_blank” as a security precaution to stop “drive by downloads” of bad content.
So I don’t think it’s gonna get fixed, as it’s a security matter.
Best bet is to link to a page, that then displays the thing to click to Trigger the download.
Then that page would also house the “upload the translations” page too. As well as all the instructions for providing translations, said page can also be linked to “outside” of the extension