When attempting to run a standard plugin goal such as "site:stage" (https://maven.apache.org/plugins/maven-site-plugin/stage-mojo.html), Maven outputs:

[ERROR] Could not find goal 'stage' in plugin com.github.github:site-maven-plugin:0.12 among available goals site, help -> [Help 1]

According to https://maven.apache.org/guides/introduction/introduction-to-plugin-prefix-mapping.html this is because this plugin is named so that the plugin prefix is "site", which conflicts with the prefix for the standard "maven-site-plugin" plugin.

This plugin should be renamed to something more like "github-site-maven-plugin" so that it has a unique prefix relative to the Maven standard site plugin. Or, the <goalPrefix> element should be used to set the prefix to something unique.