anchor.diff:        <% if user %>
           <li>
             <%= link_to profile_detail_path(user.username), class: "d-flex justify-content-between py-2" do %>
  -            <div class="c-sidebar__icon text-muted">
  +            <div class="c-sidebar__icon mr-1 text-center text-muted">
                 <i class="fal fa-user"></i>
               </div>
   
  
positive.code:         <% if user || !sign_in_required %>
            <li>
              <%= link_to link_path, class: "d-flex justify-content-between py-2" do %>
                <div class="c-sidebar__icon text-muted">
                  <i class="fal fa-<%= icon_name %>"></i>
                </div>
  
  
negative.code: 
          <li>
            <%= link_to track_path, class: "d-flex justify-content-between py-2" do %>
              <div class="c-sidebar__icon mr-1 text-center text-muted">
                <i class="fal fa-tasks"></i>
              </div>
  
  