diff --git a/requirements/docs.txt b/requirements/docs.txt
index a6a121e7..e7bf404d 100644
--- a/requirements/docs.txt
+++ b/requirements/docs.txt
@@ -13,4 +13,4 @@ sphinx-togglebutton
 sphinx_rtd_theme
 # snowballstemmer, a dependency of sphinx, was released on 2025-05-08 with version 3.0.0,
 # which causes errors in the build process. So we've limited the version for now.
-snowballstemmer<3.0
+snowballstemmer<4.0