When installing or loading Monitoring Service, MUC Service or User Service (two latter being deprecated) plugins it shows in console:
Kov 24, 2018 10:45:03 AM com.sun.jersey.api.core.PackagesResourceConfig init
INFO: Scanning for root resource and provider classes in the packages:
org.jivesoftware.openfire.plugin
Kov 24, 2018 10:45:03 AM com.sun.jersey.server.impl.application.WebApplicationImpl _initiate
INFO: Initiating Jersey application, version 'Jersey: 1.19.4 05/24/2017 03:46 PM'
Successfully loaded plugin 'monitoring'.
Although it is an INFO type of message, it is shown in red color and it looks more like an error than an informative message.
Windows (using Launcher)
I believe this was fixed in https://github.com/igniterealtime/Openfire/pull/1221