diff --git a/gsk/gl/resources/preamble.glsl b/gsk/gl/resources/preamble.glsl
index 46bebc14e0..1237951dff 100644
--- a/gsk/gl/resources/preamble.glsl
+++ b/gsk/gl/resources/preamble.glsl
@@ -1,3 +1,5 @@
+#extension GL_OES_standard_derivatives : enable
+
 #ifndef GSK_LEGACY
 precision highp float;
 #endif