I notice that in the base install of Silverblue, epiphany is installed, but if you rpm-ostree install epiphany it installs again.
What are the difference between what is embedded in Silverblue installed vs what is installed when a user rpm-ostree installs?
My understanding is the following:
epiphany-runtime is part of the base install as it is need for gnome-software webapps
When you issue rpm-ostree install epiphany you install this package which provides a /usr/share/applications/org.gnome.Epiphany.desktop file and a few other bits (Gnome integration, help, etc).
In fact, If you were to overlay epiphany-runtime you would get the the following error:
$ rpm-ostree install epiphany-runtime
error: "epiphany-runtime" is already provided by: epiphany-runtime-1:3.32.3-1.fc30.x86_64. Use --allow-inactive to explicitly require it.
Correct. Or you can build a flatpak instead of layering.
Though it would be much better/nicer to have epiphany as a (Fedora) Flatpak. I’ve asked the maintainer about that.
There’s an Epiphany Flatpak in the GNOME nightly repo IIRC.
Well… nightly. Nightly is not stable. 