Settings.aspx different navigation structure in SharePoint 2013

Question

I have following top navigation snippet (default top navigation snippet) placed inside HTML Masterpage for SharePoint 2013.

<!--SPM:<SharePoint:AjaxDelta id="DeltaTopNavigation" BlockElement="true" CssClass="ms-displayInlineBlock" runat="server">-->
    <!--SPM:<SharePoint:DelegateControl runat="server" ControlId="TopNavigationDataSource" Id="topNavigationDelegate">-->
        <!--SPM:<Template_Controls>-->
            <!--SPM:<asp:SiteMapDataSource 
                          ShowStartingNode="False"
                          SiteMapProvider="SPNavigationProvider" 
                          id="topSiteMap" 
                          runat="server"
                          StartingNodeUrl="sid:1002"/>-->
        <!--SPM:</Template_Controls>-->
     <!--SPM:</SharePoint:DelegateControl>-->
     <a name="startNavigation"></a>
     <!--SPM:<asp:ContentPlaceHolder id="PlaceHolderTopNavBar" runat="server">-->
        <!--SPM:<SharePoint:AspMenu 
                    ID="TopNavigationMenu" 
                    Runat="server" 
                    CssClass="custom-nav"
                    EnableViewState="false"
                    DataSourceID="topSiteMap"
                    AccessKey="&#60;%$Resources:wss,navigation_accesskey%&#62;"
                    UseSimpleRendering="true"
                    UseSeparateCss="false"
                    Orientation="Horizontal"
                    StaticDisplayLevels="2"
                    AdjustForShowStartingNode="true"
                    MaximumDynamicDisplayLevels="2"
                    SkipLinkText=""/>-->
            <!--PS: Start of READ-ONLY PREVIEW (do not modify)--><link rel="stylesheet" type="text/css" href="http://sp2013-srv25:1515/_layouts/15/1033/styles/menu-21.css" /><div id="zz7_TopNavigationMenu" class=" noindex ms-core-listMenu-horizontalBox"><ul id="zz9_RootAspMenu" class="root ms-core-listMenu-root static"><li class="static"><a class="static menu-item ms-core-listMenu-item ms-displayInline ms-navedit-linkNode" tabindex="0" title="Default Publishing Site" href="#" accesskey="1"><span class="additional-background ms-navedit-flyoutArrow"><span class="menu-item-text">Default Publishing Site</span></span></a></li></ul></div><!--PE: End of READ-ONLY PREVIEW-->
      <!--SPM:</asp:ContentPlaceHolder>-->
<!--SPM:</SharePoint:AjaxDelta>-->

Above snippet is the default top navigation snippet, I have only updated CssClass property with my own CSS class custom-nav.

This masterpage is applied for Site Master Page and also System Master Page.

So now my question is when I view the every pages except Settings.aspx, this navigation is having my custom class of navigation custom-nav.

But when I open /_layouts/15/settings.aspx page, at that time my custom class is not being applied, instead s4-tn class is being applied. Anybody know why so?

Also I have noticed that Search control snippet is being hidden in the DOM only for this settings.aspx page. Does anyone have idea about this behavior?

Answer 1

reference

1. Search for ID="PlaceHolderTopNavbar"

2. Bring the Sharepoint:AspMenu control outside of this placeholder and delete asp:ContentPlaceHolder tag