How to add my Custom Content to Navigation Bar

 Mathew D'Amico thank you, that was helpful!

I found, that 

ICustomNavigationItem

interface has property

ICustomNavigationItem[] Children

Is there any way to use that property? As I understand it may be something like dropdown links or I don't know //

I tried to add children links but don't see any UI changes.

public interface ICustomNavigationItem
  {
    ICustomNavigationPlugin Plugin { get; }

    string Label { get; }

    string Url { get; }

    Guid UniqueID { get; }

    ICustomNavigationItem[] Children { get; set; }

    bool IsVisible(int userID);

    bool IsSelected(string currentFullUrl);

    string CssClass { get; }

    ICustomNavigationItemConfiguration Configuration { get; }
  }

This is a limitation imposed by the Social theme - the maximum link depth supported by the Group - Banner widget is 1. Increasing it would be a customization (you would need to increase the maximumDepth parameter of the navigation configuration item and then update the link rendering in the widget to handle the .Children parameter accordingly).

This is a limitation imposed by the Social theme - the maximum link depth supported by the Group - Banner widget is 1. Increasing it would be a customization (you would need to increase the maximumDepth parameter of the navigation configuration item and then update the link rendering in the widget to handle the .Children parameter accordingly).