Gittyup Flatpak can't access SSH keys in SSH-agent

[silmaril42]

I'm using Linux Mint with KeePassXC (system package) that is configured to add SSH keys to the SSH-agent.

With this setup shell commands like git fetch work fine.

If I start Gittyup (Flatpak), it cannot access the SSH keys and the same git fetch will result in an error:

Unable to fetch from 'origin' - Failed to retrieve list of SSH authentication methods: Failed getting response

(same for all other commands that try to access the remote)

Searching the web I found some things that sounded like they could work, but none of them worked for me.

I tried adding different combinations of these switches to the command line that runs Gittyup, but none made this work:

--socket=ssh-auth --file-forwarding --filesystem=$SSH_AUTH_SOCK --env=SSH_AUTH_SOCK=$SSH_AUTH_SOCK

Is there anything I can do to my installation to get this working?

Can this be improved in the build somehow?

(You might have guessed: I don't know much about the inner workings of Flatpak.)