app/views/spree/admin/shared/_header.html.erb
<%# Override header for supplier %>
<% admin = try_spree_current_user.try(:supplier?) || try_spree_current_user.try(:has_spree_role?, "admin") %>
<header class="header <%= admin ? "logged-in" : "logged-out" %>">
<nav class="navbar navbar-inverse navbar-fixed-top" role="navigation">
<div class="container-fluid">
<div class="navbar-header">
<%= link_to image_tag(Spree::Config[:admin_interface_logo], id: 'logo', height: '100%'), spree.admin_path, class: "logo navbar-brand" %>
</div>
<% if admin %>
<a href="#" class="navbar-btn sidebar-toggle" data-toggle="offcanvas" role="button">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</a>
<div class="navbar-right" data-hook="admin_login_navigation_bar"></div>
<% end %>
</div>
</nav>
</header>