Scans a multisite or multi-network installation to identify all plugins that are active or not.
Plugin Activation Status makes it easier for owners of multisite and multi-network WordPress installations to perform plugin audits on their installations. The plugin generates a list of plugins that are not currently active on any sites or networks. It generates a separate list of plugins that are active somewhere within the installation, and provides details about where and how those plugins are activated.
This plugin first retrieves a full list of all of the plugins that are network-activated throughout your installation. Then, it loops through all of the sites in your installation, retrieving a list of all of the active plugins on each site. Next, it runs a diff between the full list of installed plugins and the list of all active plugins.
Once it retrieves all of that information, it outputs two separate lists.
The first list is the list of Inactive Plugins; all plugins that are installed, but not activated anywhere within WordPress will be listed there. The second list shows all of the Active Plugins; all plugins that are installed and activated somewhere within WordPress are shown there.
Within the Active Plugins list, each plugin also has a list of all of the places the plugin is active (at the top, a list of all of the places it's network-active; at the bottom, all of the places it's normally-activated).
When the plugin generates the lists of plugins, it stores those lists as site options in the database, so the lists can be retrieved for reference without using any additional server resources. If you would like to remove those cached lists and generate new lists, you simply have to click the Continue button on the admin page.