Your version is out of date and some new icons are not working.
@intnbb you have to add the actual link to the calendar from the Navigation page in the ACP. I don't believe Calendar adds itself.
Issue is solved, seemed to be a wrongly set Allowed-from setting under Settings->Advanced->Headers
This is fixed on master and will be available in 1.11.1. Related gh issues, https://github.com/NodeBB/NodeBB/issues/7086 https://github.com/NodeBB/NodeBB/issues/7085
@julian I was looking for the warehouse icon
Persona version is a little different from other plugins, it is fixed to your version of NodeBB. If you update your NodeBB, you should also get the newer Persona version.