diff --git a/webrender/Cargo.toml b/webrender/Cargo.toml
index 3d5ddf9157..ed364fc34d 100644
--- a/webrender/Cargo.toml
+++ b/webrender/Cargo.toml
@@ -23,7 +23,7 @@ sw_compositor = ["swgl"]
 
 [build-dependencies]
 build-parallel = "0.1.2"
-glslopt = "0.1.10"
+glslopt = "0.1.9"
 webrender_build = { version = "0.0.2", path = "../webrender_build" }
 
 [dependencies]