I spotted this line in the output from `flatpak history`:
Jun 4 16:17:20 deploy install com.discordapp.Discord x86_64 stable system flathub 8a0fc700c701 Installed %s from %s root (test) flatpak-system-helper (gnome-software) 1.3.3
This is because the format string is passed as the 'url' parameter, the
first format parameter (the ref) is passed as the 'format' parameter,
and 'origin' is ignored because (fortunately) as far as I know, no
character significant to printf (like '%') is permitted in ref names.
Fix this by passing a NULL 'url', like the neighbouring call in
flatpak_dir_deploy_update().
dbc90df513