Problem
In Fedora 36, the ifcfg-rh plugin for NetworkManager, which is needed to read configuration files in the older ifcfg-XXX format stored under /etc/sysconfig/network-scripts, is no longer installed by default, but can be installed by installing the package NetworkManager-initscripts-ifcfg-rh. However, the NetworkManager in Fedora 36 Beta images has a bug which prevents the plugin being loaded even if it is installed, so it is not possible to use this older configuration file format without updating NetworkManager.
Cause
There was a mistake in the package spec file which caused an incorrect string to be passed to the configure script for the build, which means that when NetworkManager looks for plugins during startup, it looks for a nonsensical name - %{config_plugins_default} - instead of ifcfg-rh as it should.
Related Issues
Bugzilla report: #2066849
Workarounds (for Fedora 36 Beta)
When booting Fedora 36 Beta media, and on booting installed systems for the first time, use only the newer native NetworkManager configuration formats until you are able to update NetworkManager. Any configuration files in the older ifcfg format will not be used until NetworkManager is updated.
Solution (for Fedora 36 Final)
Final Fedora 36 images are not affected by this issue.