[wjt]

They are built by Flathub, just like the vanilla Chromium build on Flathub.

Here is the most recent build logs for x86_64 https://flathub.org/builds/#/builders/12/builds/8123 which I found from the GitHub green-tick status icon on the latest commit on https://github.com/flathub/com.github.Eloston.UngoogledChrom....

[heavyset_go]

Thanks