Add 404 page.html

Author: svekars

.ci/docker/requirements.txt

@@ -3,7 +3,7 @@
 
 # Sphinx dependencies
 sphinx==7.2.6
-sphinx-gallery==0.16.0
+sphinx-gallery==0.14.0
 sphinx_design==0.6.1
 sphinxext-opengraph==0.10.0
 docutils>=0.18.1,<0.21

conf.py

@@ -120,6 +120,10 @@ def wrapper(*args, **kwargs):
     "author": "PyTorch Contributors",
 }
 
+html_additional_pages = {
+    '404': '404.html',
+}
+
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.