Florian Müllner commented:
Could Polari read the local
$GNOME_GITLAB_PERSONAL_ACCESS_TOKENto authenticate a user?
Gitlab has API for snippets, so yes, that should be possible. But "create an account on GNOME's gitlab, set up an access token, export it in your shell and restart Polari" isn't precisely what I'd call out-of-the-box.
Does Polari offer using another random pastebin out there or is paste.gnome.org hardcoded?
It's hardcoded. Originally we used fpaste, but that got criticized from non-Fedora users. The "neutral enough" paste.gnome.org stopped that criticism without having to add a (pointless IMHO) choose-your-favicon setting.