To enable a plugin in Openfire follow the steps below:
Log in to the Openfire Administration Panel.
Browse to the “Plugins -> Available Plugins” menu item.
Once you find the plugin you are looking for in the list, click the “Install” button to download and install it.
Once the plugin is installed, you will able to use it unless the plugin requires further steps to configure it.
You can later on delete the plugin you installed if you wish. You just have to browse to “Plugins -> Plugins”, find your plugin in the list and click the “delete” button.
You can also install a plugin by uploading the .jar plugin file directly. You just have to browse to “Plugins -> Plugins”, choose your .jar file and upload it.