Update manager keeps consuming lots of CPU long after done, until you close popup

[teo1978]

I turned on my computer. As usual, I got the popup telling me that there were software updates to download and install, so I clicked on Install Updates or whatever the Ok or Continue button is called, and I entered the password as prompted.

Several minutes, maybe more than an hour later, I noticed the cooling fan was spinning fast. I didn't even remember I had run update manager and I wondered what it was, so I checked by running "top" from a terminal and saw that the process consuming most CPU was update-manager. I didn't even bother checking whether it was actually finished, I assumed it obviously wasn't.

Hours later again, CPU consumption was still or again high, so I ran top again, and saw again it was the update-manager process consuming more than 20% CPU.

This time I was surprised that it still wasn't finished, so I gave focus to its window, and found out that it was just the popup saying that the update process was complete (see screenshot). I closed it by clicking on "Ok" and CPU consumption immediately went down to zero.

So, long after (who knows how long after) it was finished updating the software, the Update Manager was consuming constantly more than 20% CPU only to keep a popup open that said it was done. This is ridiculous and pathetic.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: update-manager 1:16.04.17
ProcVersionSignature: Ubuntu 4.4.0-171.200-generic 4.4.203
Uname: Linux 4.4.0-171-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia
ApportVersion: 2.20.1-0ubuntu2.21
Architecture: amd64
CurrentDesktop: Unity
Date: Sun Jan 26 17:06:26 2020
InstallationDate: Installed on 2013-10-11 (2297 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
PackageArchitecture: all
SourcePackage: update-manager
UpgradeStatus: No upgrade log present (probably fresh install)