Thank you Robert Ancell and Steve Langasek. Your patch fixed the issue.
I've updated gnome-software, gnome-software-common and gnome-software- plugin-snap to version 3.30.2-0ubuntu4 (only those packages, I left other available updates in the queue to be able to test the updated version) It now shows no updates available in the updates tab, and a tick mark with the text Software is up to date in the main window. (screenshot attached) Thank you again for acting so quickly on this issue, I'm very impressed! ** Attachment added: "sceenshot showing gnome-software 3.30.2-0ubuntu4 fix the issue" https://bugs.launchpad.net/ubuntu/+source/gnome-software/+bug/1797543/+attachment/5201487/+files/gnome-software%203.30.2-0ubuntu4.png ** Tags removed: verification-needed verification-needed-cosmic ** Tags added: verification-done verification-done-cosmic -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-software in Ubuntu. https://bugs.launchpad.net/bugs/1797543 Title: Unable to update software - Button Restart & Update, restarts no updates applied Status in gnome-software package in Ubuntu: Fix Committed Status in gnome-software source package in Cosmic: Fix Committed Bug description: [Impact] .deb package updates are shown in GNOME Software and the user is prompted to "Restart & Update". They are not updated during the restart. [Test Case] 1. Have a system with updates available 2. Open GNOME Software 3. Go to Updates page Expected result: No updates are shown (they are shown in software-properties-gtk) Observed result: Updates are shown, and the user is prompted to "Restart & Update". [Regression Potential] The fix is to update the patch to work with architectural changes that occurred in gnome-software 3.30. The additional code stops an update function from being called and is unlikely to impact other changes. There could potentially be other changes that have been missed (this seems like a low risk). [Original description] Ubuntu 18.10 beta (up to date as of 12-10-2018) Ubuntu software 3.30.2 DESCRIPTION OF BEHAVIOUR When updates are available, Ubuntu-Software shows updates are available in the "Updates" tab. One of the updates available shows "OS Updates" The grey coloured heading right above the available updates, has "Requires Restart" on the left and a green button "Restart & Update". When the green button is clicked, a popup window appears immediately showing "Restart, the system will restart automatically in 60 seconds" counting down. The restart can be cancelled or activated. When activated (either automatically or manually) the computer restarts immediately and no software is being updated. After logging in and starting up Ubuntu Software, the Updates tab checks and then shows the same updates being available as before. --- The button on the Updates tab should rather offer to update all available software and only offer to restart the computer after the updates are completed. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-software/+bug/1797543/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp

