I am experiencing the same behavior in Xubuntu 18.04 (has been a problem for a while) when using "open with" on the .deb package from Thunar (right mouse menu). If I start gdebi-gtk from the command line and use the "file open" menu option then everything works ok.
I will dig through my logs for more info. This system is a fresh install of 18.04 Gdebi was the 5th package installed after (gnumeric, gppoder, synaptic, vlc). -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1749728 Title: Installing packages fails when launched via Firefox ("open with") To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gdebi/+bug/1749728/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs