I created a repository https://nest.pijul.com/eschnett/cactusamrex, and pushed changes there into a new master channel. (I wanted to use the name master because that is the branch name in the original git repo.)

I then deleted the (empty, unused) main channel. After this, the nest page always said “This repository is empty at the moment.”, even with data on the master branch present.

After pushing data into a main channel, I can view the contents of the master channel.