Add katex_url from custom CDN

templates/base.html

@@ -12,6 +12,19 @@
     {% else %}
     <link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons">
     {% endif %}
+    {% if math_version and katex_url %}
+    <link rel="stylesheet" href="{{ katex_url }}" />
+    <style type="text/css">
+    .katex img {
+      object-fit: fill;
+      padding: unset;
+      display: block;
+      position: absolute;
+      width: 100%;
+      height: inherit;
+    }
+    </style>
+    {% endif %}
     {% block json_info %}{% endblock %}
   </head>
   <body{% if request.cookies.get('dark') == '1' %} class="dark"{% endif %}>

templates/notfound.html

@@ -3,7 +3,7 @@
 {% block title %}Not found - {{ app_name }}{% endblock %}
 
 {% block content %}
-<h1>Not Found</h1>
+<h1>{{ T('not-found') }}</h1>
 
-<p>The url at <strong>{{ request.path }}</strong> does not exist.</p>
+<p>{{ T('not-found-text-1')}} <strong>{{ request.path }}</strong> {{ T('not-found-text-2' )}}.</p>
 {% endblock %}