August 2022 Update:
A few things have changed since my original post, including (when I last checked) some dependency divergence between Ubuntu and Debian. As a result, the snap-free Chromium solution presented here might not be so easy on recent Ubuntu releases. I am leaving this post in place because it describes general techniques for restricted use of debian repos between different distributions or releases.
If you are looking for another source of Chromium packages on Ubuntu, here are some candidates:
- ungoogled-chromium from the OBS repo or as a FlatPak.
- Linux Mint builds of Chromium, which are still maintained as debian packages.
Ubuntu 19.10 (Eoan) dropped the Chromium web browser package in favor of a Snap container, introducing a variety of problems that prompted me to find an alternative. The Debian archive turned out to be an ideal solution.
Since Debian still maintains Chromium as a regular package in their APT repository, we can configure Ubuntu to get it from there, and continue to receive timely security updates along with all of our other OS updates. This makes sense from a security perspective, since Debian is where Ubuntu already gets most of its packages, and is a very well known, well organized, high-profile project. There is no need to risk installing software from some random source or trust a PPA.
Obligatory Warning: This configuration is entirely unsupported and could conceivably cause problems either immediately or in the future. If you break something, it's your own fault.
Procedure
sudo apt update && sudo apt upgrade
That brings my already-installed Ubuntu packages up to date, so it will be easier to see how upgrades are affected after I make my changes.
snap remove chromium
Bye bye, annoying snap.
sudo apt purge chromium-browser chromium-chromedriver
Bye bye, fake Chromium packages. (You can leave out the chromium-chromedriver
part if that package isn't installed on your system.)
umask 22
That just makes sure that the files I create will be readable by everyone, including the system.
Create an /etc/apt/sources.list.d/debian-stable.list file containing:
deb [signed-by=/usr/share/keyrings/debian-archive-keyring.gpg] http://deb.debian.org/debian stable main
deb-src [signed-by=/usr/share/keyrings/debian-archive-keyring.gpg] http://deb.debian.org/debian stable main
deb [signed-by=/usr/share/keyrings/debian-archive-keyring.gpg] http://deb.debian.org/debian-security/ stable-security main
deb-src [signed-by=/usr/share/keyrings/debian-archive-keyring.gpg] http://deb.debian.org/debian-security/ stable-security main
deb [signed-by=/usr/share/keyrings/debian-archive-keyring.gpg] http://deb.debian.org/debian stable-updates main
deb-src [signed-by=/usr/share/keyrings/debian-archive-keyring.gpg] http://deb.debian.org/debian stable-updates main
That tells apt to look for packages not only in the Ubuntu archives, but also in the Debian stable archives. It would ordinarily be a bad idea, because you don't want random Ubuntu packages being replaced with Debian versions, which would likely break your system. However, we're going to add some rules to avoid such problems.
Note: The /usr/share/keyrings/debian-archive-keyring.gpg file referenced
above, along with several other Debian keyring files, are already present on my
Ubuntu system thanks to the debian-archive-keyring package. It may already be
on your system, too, but if not, you should install it: sudo apt install
debian-archive-keyring
Create an /etc/apt/preferences.d/debian-chromium file containing:
Explanation: Accept chromium from the debian repo.
Package: chromium*
Pin: origin "*.debian.org"
Pin-Priority: 100
Explanation: Avoid other packages from the debian repo.
Package: *
Pin: origin "*.debian.org"
Pin-Priority: 1
The first stanza assigns a below-normal priority to Debian Chromium packages; just high enough to allow them to be manually installed and automatically updated, but not high enough to be preferred over Ubuntu packages. This is called apt pinning, and is described in the apt_preferences manual. The second stanza assigns a very low priority to all other Debian packages, so they will only be automatically installed or updated if necessary to satisfy a dependency.
(I could have assigned a much higher priority to Debian's Chromium packages if I needed them to override Ubuntu's, but since they use different package names, no overriding is necessary. I could also have pinned all of the Debian repo at priority 100; that would make any Debian-only dependencies eligible for automatic updates, effectively treating the Debian repo like Ubuntu Backports in manual install mode. I chose the more conservative approach just to be cautious.)
sudo apt update
That refreshes the package database, so my Ubuntu system now knows about everything in the Debian archives that I added.
apt list --upgradable
That shows me which packages a system-wide upgrade would include, without actually upgrading them. Since I already did an upgrade before making any changes, I don't expect to see any upgradable packages listed here.
If one or two upgradable packages were listed, it could mean that Ubuntu
happened to release some updates while I was working, which is normal. I would
ask apt where each of those updates come from before proceeding, with apt
policy package-name. If any of them were from the Debian archives, I would
consider reverting my changes, by removing the files I created and running
sudo apt update again.
If many upgradable packages were listed, it would probably mean that apt now
thinks Debian's packages are valid replacements for Ubuntu's packages, which I
do not want. This would happen if I made a mistake in those files I created.
I would revert my changes, by removing the files I created and running sudo
apt update again. I might then consider starting over and typing more
carefully.
All was well at this point (no upgradable packages were listed), so I proceeded.
sudo apt install chromium
The package manager then asked me to confirm, listing chromium and a small
handful of dependency packages needed by Chromium. Once again, if many packages
were listed here, I would investigate and consider reverting my changes. (I
investigated each dependency anyway, because I'm careful. I found that only a
few dependencies, like libjpeg62-turbo, were coming from the Debian archive,
and they don't conflict with anything I have installed.) All looked well, so I
told the package manager to proceed.
When it finished, Chromium was finally installed as an apt package. Thanks, Debian maintainers!
I don't use any snaps, so the next thing I did was to look in the snap
directory in my home dir, make sure there was nothing in there that I needed,
and then drop it in the trash. If you want to do the same, consider first that
any user data that you created/modified/saved in Chromium since the snap was
first installed lives somewhere under that snap folder. (Probably under
snap/chromium/current/.config which is hidden by default in most file
managers.) You might want to back it up or move it to chromium's usual data
directory: $HOME/.config/chromium. In my case, the Chromium data that I
wanted to keep was still in its old/usual place, since I had only used the snap
for about five minutes.
That's it. I hope it helps someone. Good luck!