HTML escape username

src/invidious/views/template.ecr

@@ -68,7 +68,7 @@
                         </div>
                         <% if env.get("preferences").as(Preferences).show_nick %>
                             <div class="pure-u-1-4">
-                                <span id="user_name"><%= env.get("user").as(Invidious::User).email %></span>
+                                <span id="user_name"><%= HTML.escape(env.get("user").as(Invidious::User).email) %></span>
                             </div>
                         <% end %>
                         <div class="pure-u-1-4">