diff --git a/docs/requirements.txt b/docs/requirements.txt
index df2a120..0ec95b8 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -2,7 +2,7 @@ appdirs==1.4.4
 furo==2024.4.27
 ipython>=7.0.0
 myst_parser==3.0.1
-nbsphinx==0.9.3
+nbsphinx==0.9.4
 numpy>=1.20.0
 py21cmemu>=1.0.5.dev0
 scipy>=1.7.0