Unfortunately, no. Firefox for desktop does the same.

Thanks! I was hoping that there is an option in about:config.

The problem at hand is that .pgp somehow are not opened by OpenKeychain upon download, whereas .gpg files are.

Otherwise, Firefox on Android is attractive, especially the built-in PDF viewer. I hope this issue will be fixed.

What is the rationale? Make sure that file extensions match mime type? (security)

In the meantime, I am trying to figure out if it is possible to have OpenKeychain show up as handler for .pgp files.

Thanks! I would just like to understand the rationale.

I don't even mind so much the change of the extension. What I do mind is that OpenKeychain is not listed as an option to decrypt .pgp files. With ".gpg" files, that issue does not exist.

Submit this at bugzilla.mozilla.org

Thanks! But, as far as I understand it, it's not a bug. It seems to be intentional.

Sorry if that didn't fix your issue. Do you want me to try asking someone that works on Firefox about this?

Thanks, Khalid, but this seems by design. Of course, if a Firefox dev could clarify, this would be great.

The issue only happens with Content-Type: application/pgp-encrypted

I see it with filebrowser installed on my server. Interestingly their official demo server at demo.filebrowser.org does not show that issue (login: demo/demo). It serves files with Content-Type: application/octet-stream