the suddenly appearing "restart required" popup could cause data loss

[Peter Kopias]

I think this is a bug (might be even serious) as data loss could happen because of update-managers way of popups.

Expected to happen:
 - update notifier shows dialog in background
 - user presses ok
 - update manager downloads and installs stuff
 - update manager does not pop up a dialog with restart selected as default
 - update manager does not restart the computer when the user presses space (or click on the button) in partial second after popping up

What happened:

 - User awakes his computer from suspend using 14.04 xubuntu
 - Browser with 15 tabs, netbeans opened
 - Starts a long running task like rendering something
 - writes some source code
 - Update-manager shows up
 - some packages need to be upgraded, no sign of restart required
 - User presses upgrade
 - Progressbar happens, download, etc
 - User changes windows, starts to fill a compicated form on a website with lots of data (like this bugreport)
 - User types 5 key/sec
 - Out Of The Blue the "Restart required" popup show up, with "Restart button selected as default"
 - 0.3 sec later space gets pressed as it was
 - Omgwtfyoujustdid?

 - User has lost all the input in the form
 - User may have lost all the opened tabs (depending on browser settings)
 - User may have lost sourcecode not saved
 - User may have lost 1-3 hours of time even if he/she can restart the long running task (rendering)

 - The user clearly did not want to restart his system
 - Update manager restarted the system without proper confirmation from the user
 - Also possible (happened previously) that while the user tries to click somewhere, the popup gets under the mouse and restart button gets the click instead of the original target.

 Suggested solution:
 1: the popup could open with the restart button disabled for about 3 seconds like browsers do before saving content to disk sometimes. This way unintended restarts would be harder to achieve

 2: don't use popups (they're so 2000 :) ). Just let the upgrade window finish the upgrade and show the texts and buttons for the reboot, and don't even pop up. The user will eventually get back to that window and select the preferred button.

$ lsb_release -rd
Description: Ubuntu 14.04.2 LTS
Release: 14.04

update-manager:
  Installed: 1:0.196.12
  Candidate: 1:0.196.12
  Version table:
 *** 1:0.196.12 0
       1001 http://hu.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     1:0.196.11 0
        500 http://hu.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages

 Thank you.

[Peter Kopias (petros-k)]

I would say this event happened to thousands of users thousands of times, but as the computer is still restarting, noone has the realtime ability to report this as a bug, and as the booting and login process starts users forgot what happened earlier, and they don't open launchpad to report. This was about my 3th or 4th unintended reboot in the past few years, it just crossed the "bug needs reporting" line.