diff --git a/sphinx_qndojo_theme/breadcrumbs.html b/sphinx_qndojo_theme/breadcrumbs.html
index 1690537..159c7ba 100644
--- a/sphinx_qndojo_theme/breadcrumbs.html
+++ b/sphinx_qndojo_theme/breadcrumbs.html
@@ -12,7 +12,7 @@
 {% block breadcrumbs_aside %}
   <li class="wy-breadcrumbs-aside open-in-colab">
     {% if hasdoc(pagename) and suffix == '.ipynb' %}
-      <a href="https://colab.research.google.com/github/{{ github_user }}/{{ github_repo }}/{{ theme_vcs_pageview_mode|default("blob") }}/{{ github_version }}{{ conf_py_path }}{{ pagename }}{{ suffix }}" target="_blank"><img src="https://colab.research.google.com/assets/colab-badge.svg" alt="Open in Colab"></a>
+      <a href="https://colab.research.google.com/github/{{ github_user }}/{{ github_repo }}/{{ theme_vcs_pageview_mode or "blob" }}/{{ github_version }}{{ conf_py_path }}{{ pagename }}{{ suffix }}" target="_blank"><img src="https://colab.research.google.com/assets/colab-badge.svg" alt="Open in Colab"></a>
     {% endif %}
   </li>
   <li class="wy-breadcrumbs-aside">
@@ -22,7 +22,7 @@
           <!-- User defined GitHub URL -->
           <a href="{{ meta['github_url'] }}" class="fa fa-github" target="_blank"> {{ _('Edit on GitHub') }}</a>
         {% else %}
-          <a href="https://{{ github_host|default("github.com") }}/{{ github_user }}/{{ github_repo }}/{{ theme_vcs_pageview_mode|default("blob") }}/{{ github_version }}{{ conf_py_path }}{{ pagename }}{{ suffix }}" class="fa fa-github" target="_blank"> {{ _('Edit on GitHub') }}</a>
+          <a href="https://{{ github_host|default("github.com") }}/{{ github_user }}/{{ github_repo }}/{{ theme_vcs_pageview_mode or "blob" }}/{{ github_version }}{{ conf_py_path }}{{ pagename }}{{ suffix }}" class="fa fa-github" target="_blank"> {{ _('Edit on GitHub') }}</a>
         {% endif %}
         {% elif show_source and source_url_prefix %}
           <a href="{{ source_url_prefix }}{{ pagename }}{{ suffix }}" target="_blank">{{ _('View page source') }}</a>