To distinct between IPv4 and IPv6 configuration, a "6" was added to the network configuration type if an IPv6 address should be configured. This is now duplicate, as with pull 13024 the same thing is already done prior, thus leading to a duplicate "6" at the end of the network config type, i.e. "static66".
Vagrant Core Plugins
These are plugins that ship with Vagrant. Vagrant core uses its own plugin system to power a lot of the core pieces that ship with Vagrant. Each plugin will have its own README which explains its specific role.
Generate proto
grpc_tools_ruby_protoc -I . --ruby_out=gen/plugin --grpc_out=gen/plugin ./plugin_server.proto