When upgrading from deb to snap, apt misreports the amount of required download (by ~20x)

[Dan Watkins]

I'm currently working on a metered connection, so I reviewed the download size of the updates that the system wanted me to apply:

  $ sudo apt upgrade
  ...
  Need to get 8,841 kB of archives.
  ...

This is acceptable to me, so I start the upgrade process. Partway through, the chromium snap starts getting installed, which is _155 MB_. I would not have installed this update if I had realised how large the required download _actually was_, and I don't trust snapd to behave itself if I terminate the install.

This is a frustrating user experience, and I think it should be better.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: chromium-browser (not installed)
Uname: Linux 5.4.5-050405-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu15
Architecture: amd64
Date: Tue Jan 21 15:35:45 2020
InstallationDate: Installed on 2019-05-07 (259 days ago)
InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
SourcePackage: chromium-browser
UpgradeStatus: Upgraded to focal on 2019-11-15 (67 days ago)

[Dan Watkins (oddbloke)]

Worth noting that "After this operation, 246 MB disk space will be freed." in the apt output is also incorrect.

[Launchpad Janitor (janitor)]

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