diff --git a/tools/wptrunner/requirements_opera.txt b/tools/wptrunner/requirements_opera.txt
index 6c2425f337bf68..888e064a88ea44 100644
--- a/tools/wptrunner/requirements_opera.txt
+++ b/tools/wptrunner/requirements_opera.txt
@@ -1,2 +1,2 @@
 mozprocess==1.3.1
-selenium==4.20.0
+selenium==4.21.0
diff --git a/tools/wptrunner/requirements_sauce.txt b/tools/wptrunner/requirements_sauce.txt
index 806352e87e2471..5f5f66509d1c33 100644
--- a/tools/wptrunner/requirements_sauce.txt
+++ b/tools/wptrunner/requirements_sauce.txt
@@ -1,2 +1,2 @@
-selenium==4.20.0
+selenium==4.21.0
 requests==2.31.0