i've submitted 2 patches to fix this. happy to amend them if anyone can review them

I built a package for perl-net-dbus locally, installed it, and tried again. That got me past this error, but there were more missing dependencies. Here's the full transcript with all errors before I got the command to stop complaining.

@willgfx I tried manually installing transgui to see if it handled magnet files better than transmission-remote-gtk does. From the terminal,transgui <magnet-link>does work as expected, but after setting everything up with xdg-open, neither clicking magnet links in a web browser or xdg-open <magnet-link> work.
They launch transgui but do not begin downloading the magnet link. For reference, here's my transgui.desktop

For anyone looking for the upstream bug report, this issue looks related
https://bugzilla.gnome.org/show_bug.cgi?id=780167