diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 241aa0aa60e..4eac2a68915 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -1306,6 +1306,11 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
         }
     }
 
+    // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.3
+    fn SampleCoverage(&self, value: f32, invert: bool) {
+        self.ipc_renderer.send(CanvasMsg::WebGL(WebGLCommand::SampleCoverage(value, invert))).unwrap();
+    }
+
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.4
     fn Scissor(&self, x: i32, y: i32, width: i32, height: i32) {
         self.ipc_renderer
diff --git a/components/script/dom/webidls/WebGLRenderingContext.webidl b/components/script/dom/webidls/WebGLRenderingContext.webidl
index 76ff64a1261..b62b4e3a18f 100644
--- a/components/script/dom/webidls/WebGLRenderingContext.webidl
+++ b/components/script/dom/webidls/WebGLRenderingContext.webidl
@@ -619,7 +619,7 @@ interface WebGLRenderingContextBase
 
     //void renderbufferStorage(GLenum target, GLenum internalformat,
     //                         GLsizei width, GLsizei height);
-    //void sampleCoverage(GLclampf value, GLboolean invert);
+    void sampleCoverage(GLclampf value, GLboolean invert);
     void scissor(GLint x, GLint y, GLsizei width, GLsizei height);
 
     void shaderSource(WebGLShader? shader, DOMString source);
diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index b8690c071a3..e7e3abad13d 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -2524,7 +2524,7 @@ dependencies = [
 [[package]]
 name = "webrender_traits"
 version = "0.1.0"
-source = "git+https://github.com/servo/webrender_traits#7a51247cb5333d7a4560e00fe4518db328a550da"
+source = "git+https://github.com/servo/webrender_traits#f74a744614b4c0c2fc64d39916386848124f4d52"
 dependencies = [
  "app_units 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/ports/cef/Cargo.lock b/ports/cef/Cargo.lock
index 329082d4933..a990589c8ef 100644
--- a/ports/cef/Cargo.lock
+++ b/ports/cef/Cargo.lock
@@ -2385,7 +2385,7 @@ dependencies = [
 [[package]]
 name = "webrender_traits"
 version = "0.1.0"
-source = "git+https://github.com/servo/webrender_traits#7a51247cb5333d7a4560e00fe4518db328a550da"
+source = "git+https://github.com/servo/webrender_traits#f74a744614b4c0c2fc64d39916386848124f4d52"
 dependencies = [
  "app_units 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/ports/gonk/Cargo.lock b/ports/gonk/Cargo.lock
index 4a8c715a5a7..79ffcb76edb 100644
--- a/ports/gonk/Cargo.lock
+++ b/ports/gonk/Cargo.lock
@@ -2340,7 +2340,7 @@ dependencies = [
 [[package]]
 name = "webrender_traits"
 version = "0.1.0"
-source = "git+https://github.com/servo/webrender_traits#7a51247cb5333d7a4560e00fe4518db328a550da"
+source = "git+https://github.com/servo/webrender_traits#f74a744614b4c0c2fc64d39916386848124f4d52"
 dependencies = [
  "app_units 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",