diff --git a/material/base.html b/material/base.html
index 756151c69..a21b20548 100644
--- a/material/base.html
+++ b/material/base.html
@@ -110,7 +110,7 @@
                  <a href="{{ page.edit_url }}" title="{{ lang.t('edit.link.title') }}" class="md-icon md-content__edit">edit</a>
                {% endif %}
               {% block content %}
-                {% if not "\x3ch1 id=" in page.content %}
+                {% if not "\x3ch1" in page.content %}
                   <h1>{{ page.title | default(config.site_name, true)}}</h1>
                 {% endif %}
                 {{ page.content }}
diff --git a/material/partials/nav-item.html b/material/partials/nav-item.html
index 651c60120..be77f2f6b 100644
--- a/material/partials/nav-item.html
+++ b/material/partials/nav-item.html
@@ -25,10 +25,10 @@
   <li class="md-nav__item">
     {% set toc_ = page.toc %}
     <input class="md-toggle md-nav__toggle" data-md-toggle="toc" type="checkbox" id="toc">
-    {% if "\x3ch1 id=" in page.content %}
+    {% if toc_ | first is defined %}
       {% set toc_ = (toc_ | first).children %}
     {% endif %}
-    {% if toc_ and (toc_ | first) %}
+    {% if toc_ | first is defined %}
       <label class="md-nav__link md-nav__link--active" for="toc">
         {{ nav_item.title }}
       </label>
@@ -36,7 +36,7 @@
     <a href="{{ nav_item.url }}" title="{{ nav_item.title }}" class="md-nav__link md-nav__link--active">
       {{ nav_item.title }}
     </a>
-    {% if page.toc %}
+    {% if toc_ | first is defined %}
       {% include "partials/toc.html" %}
     {% endif %}
   </li>
diff --git a/material/partials/toc.html b/material/partials/toc.html
index 004067dda..5e44226b1 100644
--- a/material/partials/toc.html
+++ b/material/partials/toc.html
@@ -1,10 +1,10 @@
 {% import "partials/language.html" as lang %}
 <nav class="md-nav md-nav--secondary">
   {% set toc_ = page.toc %}
-  {% if "\x3ch1 id=" in page.content %}
+  {% if toc_ | first is defined and "\x3ch1 id=" in page.content %}
     {% set toc_ = (toc_ | first).children %}
   {% endif %}
-  {% if toc_ and (toc_ | first) %}
+  {% if toc_ | first is defined %}
     <label class="md-nav__title" for="toc">{{ lang.t('toc.title') }}</label>
     <ul class="md-nav__list" data-md-scrollfix>
       {% for toc_item in toc_ %}
diff --git a/src/base.html b/src/base.html
index 9383f1554..24c69ba0a 100644
--- a/src/base.html
+++ b/src/base.html
@@ -218,11 +218,11 @@
               {% block content %}
 
                 <!--
-                  This is a nasty hack that checks whether the content contains
-                  a h1 headline. If it doesn't, the page title (or respectively
-                  site name) is used as the main headline.
+                  Hack: check whether the content contains a h1 headline. If it
+                  doesn't, the page title (or respectively site name) is used
+                  as the main headline.
                 -->
-                {% if not "\x3ch1 id=" in page.content %}
+                {% if not "\x3ch1" in page.content %}
                   <h1>{{ page.title | default(config.site_name, true)}}</h1>
                 {% endif %}
 
diff --git a/src/partials/nav-item.html b/src/partials/nav-item.html
index eb20e8773..97a73c8ab 100644
--- a/src/partials/nav-item.html
+++ b/src/partials/nav-item.html
@@ -62,13 +62,13 @@
     <input class="md-toggle md-nav__toggle" data-md-toggle="toc"
         type="checkbox" id="toc" />
 
-    <!-- Nasty hack - see partials/toc.html for more information -->
-    {% if "\x3ch1 id=" in page.content %}
+    <!-- Hack: see partials/toc.html for more information -->
+    {% if toc_ | first is defined %}
       {% set toc_ = (toc_ | first).children %}
     {% endif %}
 
     <!-- Render table of contents, if not empty -->
-    {% if toc_ and (toc_ | first) %}
+    {% if toc_ | first is defined %}
       <label class="md-nav__link md-nav__link--active" for="toc">
         {{ nav_item.title }}
       </label>
@@ -79,7 +79,7 @@
     </a>
 
     <!-- Show table of contents -->
-    {% if page.toc %}
+    {% if toc_ | first is defined %}
       {% include "partials/toc.html" %}
     {% endif %}
   </li>
diff --git a/src/partials/toc.html b/src/partials/toc.html
index b35d5e807..3c48c11ef 100644
--- a/src/partials/toc.html
+++ b/src/partials/toc.html
@@ -27,17 +27,17 @@
   {% set toc_ = page.toc %}
 
   <!--
-    This is a nasty hack that checks whether the content contains a h1
-    headline. If it does, the top-level anchor must be skipped, since it would
-    be redundant to the link to the current page that is located just above the
-    anchor. Therefore we directly continue with the children of the anchor.
+    Hack: check whether the content contains a h1 headline. If it does, the
+    top-level anchor must be skipped, since it would be redundant to the link
+    to the current page that is located just above the anchor. Therefore we
+    directly continue with the children of the anchor.
   -->
-  {% if "\x3ch1 id=" in page.content %}
+  {% if toc_ | first is defined and "\x3ch1 id=" in page.content %}
     {% set toc_ = (toc_ | first).children %}
   {% endif %}
 
   <!-- Render item list -->
-  {% if toc_ and (toc_ | first) %}
+  {% if toc_ | first is defined %}
     <label class="md-nav__title" for="toc">{{ lang.t('toc.title') }}</label>
     <ul class="md-nav__list" data-md-scrollfix>
       {% for toc_item in toc_ %}