If a plugin uses the SystemProperty class, then the plugin can't supply a description for that property, resulting in it showing `— ?property-name?` in the System Properties page.
Analysis;
a) The SystemProperty class uses `LocaleUtils.getLocalizedString(...)` to find the description of the property
b) `LocaleUtils.getLocalizedString(...)` assumes a ResourceBundle of `openfire_i18n`
c) Because `openfire_i18n` already exists on the classpath, adding a second one in the plugin will not help.