diff --git a/material/partials/header.html b/material/partials/header.html
index 20e88e8cf..dc1bd0e38 100644
--- a/material/partials/header.html
+++ b/material/partials/header.html
@@ -2,8 +2,8 @@
   This file was automatically generated - do not edit
 -#}
 {% set site_url = config.site_url | default(nav.homepage.url, true) | url %}
-{% if not config.use_directory_urls and site_url == "." %}
-  {% set site_url = site_url ~ "/index.html" %}
+{% if not config.use_directory_urls and site_url[0] == site_url[-1] == "." %}
+  {% set site_url = site_url ~ "/index.html" | url %}
 {% endif %}
 <header class="md-header" data-md-component="header">
   <nav class="md-header-nav md-grid" aria-label="{{ lang.t('header.title') }}">
diff --git a/material/partials/nav.html b/material/partials/nav.html
index 9e3143894..2d4a0f804 100644
--- a/material/partials/nav.html
+++ b/material/partials/nav.html
@@ -2,7 +2,7 @@
   This file was automatically generated - do not edit
 -#}
 {% set site_url = config.site_url | default(nav.homepage.url, true) | url %}
-{% if not config.use_directory_urls and site_url == "." %}
+{% if not config.use_directory_urls and site_url[0] == site_url[-1] == "." %}
   {% set site_url = site_url ~ "/index.html" %}
 {% endif %}
 <nav class="md-nav md-nav--primary" aria-label="{{ lang.t('nav.title') }}" data-md-level="0">
diff --git a/src/partials/header.html b/src/partials/header.html
index 247505021..953dfb976 100644
--- a/src/partials/header.html
+++ b/src/partials/header.html
@@ -22,8 +22,8 @@
 
 <!-- Mitigate bug: https://github.com/mkdocs/mkdocs/issues/2191 -->
 {% set site_url = config.site_url | default(nav.homepage.url, true) | url %}
-{% if not config.use_directory_urls and site_url == "." %}
-  {% set site_url = site_url ~ "/index.html" %}
+{% if not config.use_directory_urls and site_url[0] == site_url[-1] == "." %}
+  {% set site_url = site_url ~ "/index.html" | url %}
 {% endif %}
 
 <!-- Application header -->
diff --git a/src/partials/nav.html b/src/partials/nav.html
index a5f0cfbc1..a9120f6f3 100644
--- a/src/partials/nav.html
+++ b/src/partials/nav.html
@@ -22,7 +22,7 @@
 
 <!-- Mitigate bug: https://github.com/mkdocs/mkdocs/issues/2191 -->
 {% set site_url = config.site_url | default(nav.homepage.url, true) | url %}
-{% if not config.use_directory_urls and site_url == "." %}
+{% if not config.use_directory_urls and site_url[0] == site_url[-1] == "." %}
   {% set site_url = site_url ~ "/index.html" %}
 {% endif %}