I found that if I move a bit the "import requests_unixsocket" line (in file LivepatchService.py), then the software-properties-gtk call *works*. Please somebody either propagate this solution (if it is a true solution), or tell me how to propagate. (I do not know shat is exactly happening. Whether the try-clause partly succeeds, then rolls back?..)
$ sudo -s # cd /usr/lib/python3/dist-packages/softwareproperties # diff -u4 LivepatchService.py.ORI LivepatchService.py.MY --- LivepatchService.py.ORI 2019-06-24 14:46:07.000000000 +0200 +++ LivepatchService.py.MY 2019-06-24 14:54:31.000000000 +0200 @@ -23,13 +23,12 @@ import logging import gi from gi.repository import Gio, GLib, GObject +import requests_unixsocket try: import dateutil.parser - import requests_unixsocket - gi.require_version('Snapd', '1') from gi.repository import Snapd except(ImportError, ValueError): pass # cp LivepatchService.py.MY LivepatchService.py $ software-properties-gtk {OK, works! The dialog is popping up.} -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1830914 Title: software-properties-gtk does not run at all! To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/software-properties/+bug/1830914/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs