Software Updater is sometimes blank when there are ONLY phased updates and auto-removable kernels

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I've seen the same behaviour on my 18.04 system. It didn't use to show the update-manager window in older releases when only phased updates were available so it might be the removable kernels which are triggering it. (Or a combination of the two?)

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This happened to an Ubuntu user I know here is a photo of what they saw in the terminal on July 20, 2018.

Phased updates were not considered when kernel removal was added, we need to check for them, too.

Autoremoval is expected to be offered when there are installable packages, but phased packages are not always installable.

Status changed to 'Confirmed' because the bug affects multiple users.

I'm running 16.04 LTS, and this bug has appeared in the last month or so.
I initially wondered if a phisher was wanting me to download some virus since there no details of the upgrades were displayed. Because the size of the upgrades increased over time, I presumed not and decided to "Install Now".

Discovered today that the thread I posted to on prior days was a duplicate to this thread, so now I'm updating here. This bug with my system first appeared August 9th. Yesterday I decided to go ahead and install whatever updates were there (even though I could not see 'what' the updates were since the box was blank). This was what occurred yesterday with my system while running the updater:

16.04.5 LTS xenial

The 'software updater' continued to show only the blank white box, but indicated there was updates to install. I decided to go ahead and run it through the installation process. (See attached image).

With the plain white box there was no way to see 'what' the updates would be. But, after selecting 'install', the Terminal Emulator opened and showed the installation progress as it normally does.

When the update was complete the message, "The Software on This Computer is Up to Date" also came up as normal. So the only bug appears to be just the blank white box not revealing 'what' the updates are.

Now for today: I just ran the Software Updater and it is now functioning properly - showing what the available updates are in the box as it should - not just a blank white box as before, so for me it seems to have been resolved - at least for now! Thanks!

Seeing the same behaviour on this 16.04 system:

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04.5 LTS
Release: 16.04
Codename: xenial

$ apt-cache policy update-manager
update-manager:
  Installed: 1:16.04.13
  Candidate: 1:16.04.13
  Version table:
 *** 1:16.04.13 500
        500 http://dk.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
        500 http://dk.archive.ubuntu.com/ubuntu xenial-updates/main i386 Packages
        100 /var/lib/dpkg/status
     1:16.04.12 500
        500 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu xenial-security/main i386 Packages
     1:16.04.3 500
        500 http://dk.archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        500 http://dk.archive.ubuntu.com/ubuntu xenial/main i386 Packages

$ apt list --upgradeable
Listing... Done
chromium-browser/xenial-updates,xenial-security 68.0.3440.106-0ubuntu0.16.04.1 amd64 [upgradable from: 68.0.3440.75-0ubuntu0.16.04.1]
chromium-browser-l10n/xenial-updates,xenial-updates,xenial-security,xenial-security 68.0.3440.106-0ubuntu0.16.04.1 all [upgradable from: 68.0.3440.75-0ubuntu0.16.04.1]
chromium-codecs-ffmpeg-extra/xenial-updates,xenial-security 68.0.3440.106-0ubuntu0.16.04.1 amd64 [upgradable from: 68.0.3440.75-0ubuntu0.16.04.1]
flashplugin-installer/xenial-updates,xenial-security 30.0.0.154ubuntu0.16.04.1 amd64 [upgradable from: 30.0.0.134ubuntu0.16.04.1]
gir1.2-javascriptcoregtk-4.0/xenial-updates,xenial-security 2.20.5-0ubuntu0.16.04.1 amd64 [upgradable from: 2.20.3-0ubuntu0.16.04.1]
gir1.2-webkit2-4.0/xenial-updates,xenial-security 2.20.5-0ubuntu0.16.04.1 amd64 [upgradable from: 2.20.3-0ubuntu0.16.04.1]
josm/unknown,unknown 1.5.svn14163 all [upgradable from: 1.5.svn14066]
libapache2-mod-php/xenial,xenial 1:7.2+62+ubuntu16.04.1+deb.sury.org+3 all [upgradable from: 1:7.2+62+ubuntu16.04.1+deb.sury.org+1]
libapache2-mod-php7.2/xenial 7.2.9-1+ubuntu16.04.1+deb.sury.org+1 amd64 [upgradable from: 7.2.8-1+ubuntu16.04.1+deb.sury.org+1]
libjavascriptcoregtk-4.0-18/xenial-updates,xenial-security 2.20.5-0ubuntu0.16.04.1 amd64 [upgradable from: 2.20.3-0ubuntu0.16.04.1]
libjavascriptcoregtk-4.0-dev/xenial-updates,xenial-security 2.20.5-0ubuntu0.16.04.1 amd64 [upgradable from: 2.20.3-0ubuntu0.16.04.1]
libnss-myhostname/xenial-updates 229-4ubuntu21.4 amd64 [upgradable from: 229-4ubuntu21.2]
libpam-systemd/xenial-updates 229-4ubuntu21.4 amd64 [upgradable from: 229-4ubuntu21.2]
libpq5/xenial-updates,xenial-security 9.5.14-0ubuntu0.16.04 amd64 [upgradable from: 9.5.13-0ubuntu0.16.04]
libsystemd-dev/xenial-updates 229-4ubuntu21.4 amd64 [upgradable from: 229-4ubuntu21.2]
libsystemd0/xenial-updates 229-4ubuntu21.4 amd64 [upgradable from: 229-4ubuntu21.2]
libudev-dev/xenial-updates 229-4ubuntu21.4 amd64 [upgradable from: 229-4ubuntu21.2]
libudev1/xenial-updates 229-4ubuntu21.4 amd64 [upgradable from: 229-4ubuntu21.2]
libwebkit2gtk-4.0-37/xenial-updates,xenial-security 2.20.5-0ubuntu0.16.04.1 amd64 [upgradable from: 2.20.3-0ubuntu0.16.04.1]
libwebkit2gtk-4.0-37-gtk2/xenial-updates,xenial-security 2.20.5-0ubuntu0.16.04.1 amd64 [upgradable from: 2.20.3-0ub...

Still seeing this (haven't updated, neither using apt nor update-manager because this bug annoys me).

Digged for when this was introduced in update-manager and found the package was updated in June:

$ zgrep update-manager /var/log/apt/hi*2* -B3 -A1
/var/log/apt/history.log.2.gz:Start-Date: 2018-06-26 13:34:44
/var/log/apt/history.log.2.gz:Commandline: apt upgrade
/var/log/apt/history.log.2.gz:Requested-By: miki (1000)
/var/log/apt/history.log.2.gz:Upgrade: update-manager-core:amd64 (1:16.04.12, 1:16.04.13), unity-control-center-faces:amd64 (15.04.0+16.04.20170214-0ubuntu2, 15.04.0+16.04.20171130-0ubuntu1), update-manager:amd64 (1:16.04.12, 1:16.04.13), gnome-software:amd64 (3.20.5-0ubuntu0.16.04.10, 3.20.5-0ubuntu0.16.04.11), virtualbox-dkms:amd64 (5.0.40-dfsg-0ubuntu1.16.04.2, 5.1.34-dfsg-0ubuntu1.16.04.2), virtualbox:amd64 (5.0.40-dfsg-0ubuntu1.16.04.2, 5.1.34-dfsg-0ubuntu1.16.04.2), unity-control-center:amd64 (15.04.0+16.04.20170214-0ubuntu2, 15.04.0+16.04.20171130-0ubuntu1), ubuntu-software:amd64 (3.20.5-0ubuntu0.16.04.10, 3.20.5-0ubuntu0.16.04.11), python3-update-manager:amd64 (1:16.04.12, 1:16.04.13), libunity-control-center1:amd64 (15.04.0+16.04.20170214-0ubuntu2, 15.04.0+16.04.20171130-0ubuntu1), virtualbox-qt:amd64 (5.0.40-dfsg-0ubuntu1.16.04.2, 5.1.34-dfsg-0ubuntu1.16.04.2), gnome-software-common:amd64 (3.20.5-0ubuntu0.16.04.10, 3.20.5-0ubuntu0.16.04.11)
/var/log/apt/history.log.2.gz:End-Date: 2018-06-26 13:36:58

Seems like the bug is introduced in 1:16.04.13: https://launchpad.net/ubuntu/+source/update-manager/1:16.04.13

Full patch here: https://launchpadlibrarian.net/370576411/update-manager_1%3A16.04.12_1%3A16.04.13.diff.gz

Though, looking through the path I can't identify any connection with phased updates. The changes seems to relate to autoremoving only.

Unfortunately still affecting 18.04.1 LTS, observed on and off again using Software Updater.
Recent system update performed 16/Dec/2018 comes up blank again, where it says "Updated software is available for this computer", but the list of available updates contains nothing. It does say the size of how much data will be downloaded. But no details of what this download is or what changes will be made if I click 'Install Now'.

FYI this is not an exact duplicate of bug #1072136 though...

Will this be addressed for Bionic in the near future? Many thanks

Still occurring intermittently - please advise if this will be addressed in future updates?
Thanks.
NB: This is a different issue from bug #1072136