This looks good to me. 👍

I tested installing Atom in VirtualBox, built on either Ubuntu 18.04 or 20.04, and upgrading to building on Ubuntu 18.04 appears to have minimal if any impact on backward-compatibility for Atom users. (Which was a surprise to me.) ubuntu-latest (Ubuntu 20.04) did cause some backward-compatibility issues on older Debian/Ubuntu, though.)

• Atom built on Ubuntu 18.04 (build artifacts) can still run on Debian 9 and Ubuntu 16.04 ✔️
• Atom built on ubuntu-latest (Ubuntu 20.04) (build artifacts) won't run on Debian 9 or Ubuntu 16.04 ❌

So I think it's good to stick with building on Ubuntu 18.04 for now.

(Debian 9 is still in LTS support, so I think it's good for Atom to still be able to run there.)

As the Ubuntu 16.04 build environment won't be available in Azure Pipelines after September, we have to upgrade eventually. So, might as well do it now rather than later, especially since there's no obvious downside in my testing.

(P.S. Sorry for all the noise earlier, I had assumed based on general past experience there would be an issue, without confirming it specifically for Atom on these OS versions. The glibc version is newer in Ubuntu 18.04, but apparently not different enough from the glibc in Ubuntu 16.04 or Debian 9 to introduce breaking incompatibility.)