Ubuntu
gnome-shell package

  1. Bug #1734095
  2. Comment #8

Comment 8 for bug 1734095

Revision history for this message
Luis (perdigao) wrote : Re: After upgrade to ubuntu 17.10 Software & Updates not showing authorization popup [gnome-shell[N]: pushModal: invocation of begin_modal failed]

I am having similar problem in Lubuntu 18.04 LTS. I found it originally when I run 'Software and Updates' from the menu (software-properties-gtk) and try to check/uncheck software sources. Checking/unchecking does not work. I can only see the error message "ERROR:root:Authentication canceled, changes have not been saved" if I run it from the command line.