diff --git a/srcpkgs/kea/patches/sphinx-4.0.patch b/srcpkgs/kea/patches/sphinx-4.0.patch
new file mode 100644
index 00000000000..ffe68522a57
--- /dev/null
+++ b/srcpkgs/kea/patches/sphinx-4.0.patch
@@ -0,0 +1,13 @@
+ add_stylesheet was renamed to add_css_file from Sphinx 1.8
+Index: kea-1.9.5/doc/sphinx/conf.py
+===================================================================
+--- kea-1.9.5.orig/doc/sphinx/conf.py
++++ kea-1.9.5/doc/sphinx/conf.py
+@@ -228,6 +228,6 @@ def run_generate_docs(_):
+ 
+ # custom setup hook
+ def setup(app):
+-    app.add_stylesheet('kea.css')
++    app.add_css_file('kea.css')
+ 
+     app.connect('builder-inited', run_generate_docs)