We need to decide whether we want site plugins to be able to appear in the bottom tabs or not. We decided not to because site plugins are loaded slower than the core of the app, so we can have the following case:

-User starts the app and sees 5 tabs: Home, Calendar, Messaging, Notifications and More.
-A site plugin that should be displayed in bottom tabs finishes loading. Suddenly the Notifications tab disappears and is replaced by the plugin tab.

This behaviour can be a bit confusing for the user.