diff --git a/kwin/main.js.in b/kwin/main.js.in
index 67e6fb5..1e90177 100755
--- a/kwin/main.js.in
+++ b/kwin/main.js.in
@@ -106,6 +106,13 @@ class BMW%NICK%Effect {
                     uniform: "forOpening",
                     from: 1.0,
                     to: 1.0
+                },
+                {
+                    type: Effect.ShaderUniform,
+                    fragmentShader: this.shader,
+                    uniform: "uDuration",
+                    from: this.duration,
+                    to: this.duration
                 }
             ]
         });
@@ -140,6 +147,13 @@ class BMW%NICK%Effect {
                     uniform: "forOpening",
                     from: 0.0,
                     to: 0.0
+                },
+                {
+                    type: Effect.ShaderUniform,
+                    fragmentShader: this.shader,
+                    uniform: "uDuration",
+                    from: this.duration,
+                    to: this.duration
                 }
             ]
         });