diff --git a/extensions/WEBGL_shader_pixel_local_storage/extension.xml b/extensions/WEBGL_shader_pixel_local_storage/extension.xml
index 663c3df81..47058abb5 100644
--- a/extensions/WEBGL_shader_pixel_local_storage/extension.xml
+++ b/extensions/WEBGL_shader_pixel_local_storage/extension.xml
@@ -78,14 +78,17 @@ interface WEBGL_shader_pixel_local_storage {
   const GLenum PIXEL_LOCAL_TEXTURE_NAME_WEBGL = 0x96E8;
   const GLenum PIXEL_LOCAL_TEXTURE_LEVEL_WEBGL = 0x96E9;
   const GLenum PIXEL_LOCAL_TEXTURE_LAYER_WEBGL = 0x96EA;
-  const GLenum PIXEL_LOCAL_CLEAR_VALUE_FLOAT_WEBGL = 0x96EB;
-  const GLenum PIXEL_LOCAL_CLEAR_VALUE_INT_WEBGL = 0x96EC;
-  const GLenum PIXEL_LOCAL_CLEAR_VALUE_UNSIGNED_INT_WEBGL = 0x96ED;
+  const GLenum PIXEL_LOCAL_USAGE_WEBGL = 0x96EB;
+  const GLenum PIXEL_LOCAL_CLEAR_VALUE_FLOAT_WEBGL = 0x96EC;
+  const GLenum PIXEL_LOCAL_CLEAR_VALUE_INT_WEBGL = 0x96ED;
+  const GLenum PIXEL_LOCAL_CLEAR_VALUE_UNSIGNED_INT_WEBGL = 0x96EE;
+  const GLenum PIXEL_LOCAL_USAGE_ALWAYS_NONCOHERENT_BIT_WEBGL = 0x1;
   GLboolean isCoherent();
   undefined framebufferTexturePixelLocalStorageWEBGL(GLint plane,
                                                      WebGLTexture? texture,
                                                      GLint level,
-                                                     GLint layer);
+                                                     GLint layer,
+                                                     GLbitfield usage);
   undefined framebufferPixelLocalClearValuefvWEBGL(GLint plane,
                                                    Float32List value,
                                                    optional unsigned long long srcOffset = 0);
@@ -121,6 +124,7 @@ interface WEBGL_shader_pixel_local_storage {
       <param name="texture" type="WebGLTexture?"/>
       <param name="level" type="GLint"/>
       <param name="layer" type="GLint"/>
+      <param name="usage" type="GLbitfield"/>
       <p>
         Establishes the backing texture for the given plane.
       </p>
@@ -266,6 +270,7 @@ interface WEBGL_shader_pixel_local_storage {
       <tr><td>PIXEL_LOCAL_TEXTURE_NAME_WEBGL</td><td>WebGLTexture?</td></tr>
       <tr><td>PIXEL_LOCAL_TEXTURE_LEVEL_WEBGL</td><td>GLint</td></tr>
       <tr><td>PIXEL_LOCAL_TEXTURE_LAYER_WEBGL</td><td>GLint</td></tr>
+      <tr><td>PIXEL_LOCAL_USAGE_WEBGL</td><td>GLbitfield</td></tr>
       <tr><td>PIXEL_LOCAL_CLEAR_VALUE_FLOAT_WEBGL</td><td>Float32Array</td></tr>
       <tr><td>PIXEL_LOCAL_CLEAR_VALUE_INT_WEBGL</td><td>Int32Array</td></tr>
       <tr><td>PIXEL_LOCAL_CLEAR_VALUE_UNSIGNED_INT_WEBGL</td><td>Uint32Array</td></tr>
@@ -283,5 +288,8 @@ interface WEBGL_shader_pixel_local_storage {
     <revision date="2025/03/24">
       <change>Removed MAX_COLOR_ATTACHMENTS_WITH_ACTIVE_PIXEL_LOCAL_STORAGE_WEBGL enum, which was removed from the underlying ANGLE extension.</change>
     </revision>
+    <revision date="2026/02/20">
+      <change>Added non-coherent "usage" flag and revised enum values, tracking ANGLE extension.</change>
+    </revision>
   </history>
 </draft>
diff --git a/sdk/tests/conformance2/extensions/webgl-shader-pixel-local-storage.html b/sdk/tests/conformance2/extensions/webgl-shader-pixel-local-storage.html
index e92e3624d..0a421fee4 100644
--- a/sdk/tests/conformance2/extensions/webgl-shader-pixel-local-storage.html
+++ b/sdk/tests/conformance2/extensions/webgl-shader-pixel-local-storage.html
@@ -130,9 +130,11 @@
   shouldBe("pls.PIXEL_LOCAL_TEXTURE_NAME_WEBGL", "0x96E8");
   shouldBe("pls.PIXEL_LOCAL_TEXTURE_LEVEL_WEBGL", "0x96E9");
   shouldBe("pls.PIXEL_LOCAL_TEXTURE_LAYER_WEBGL", "0x96EA");
-  shouldBe("pls.PIXEL_LOCAL_CLEAR_VALUE_FLOAT_WEBGL", "0x96EB");
-  shouldBe("pls.PIXEL_LOCAL_CLEAR_VALUE_INT_WEBGL", "0x96EC");
-  shouldBe("pls.PIXEL_LOCAL_CLEAR_VALUE_UNSIGNED_INT_WEBGL", "0x96ED");
+  shouldBe("pls.PIXEL_LOCAL_USAGE_WEBGL", "0x96EB");
+  shouldBe("pls.PIXEL_LOCAL_CLEAR_VALUE_FLOAT_WEBGL", "0x96EC");
+  shouldBe("pls.PIXEL_LOCAL_CLEAR_VALUE_INT_WEBGL", "0x96ED");
+  shouldBe("pls.PIXEL_LOCAL_CLEAR_VALUE_UNSIGNED_INT_WEBGL", "0x96EE");
+  shouldBe("pls.PIXEL_LOCAL_USAGE_ALWAYS_NONCOHERENT_BIT_WEBGL", "0x1");
 }
 
 function checkImplementationDependentLimits() {
@@ -182,6 +184,8 @@
         i, pls.PIXEL_LOCAL_TEXTURE_LEVEL_WEBGL) == 0);
     expectTrue(pls.getFramebufferPixelLocalStorageParameterWEBGL(
         i, pls.PIXEL_LOCAL_TEXTURE_LAYER_WEBGL) == 0);
+    expectTrue(pls.getFramebufferPixelLocalStorageParameterWEBGL(
+        i, pls.PIXEL_LOCAL_USAGE_WEBGL) == 0);
     expectTrue(arraysEqual(
         pls.getFramebufferPixelLocalStorageParameterWEBGL(
             i, pls.PIXEL_LOCAL_CLEAR_VALUE_FLOAT_WEBGL),
@@ -211,7 +215,7 @@
   gl.texStorage2D(gl.TEXTURE_2D, 1, gl.RGBA8, 1, 1);
   wtu.glErrorShouldBe(gl, gl.NONE);
   gl.deleteTexture(tex);
-  pls.framebufferTexturePixelLocalStorageWEBGL(0, tex, 0, 0);
+  pls.framebufferTexturePixelLocalStorageWEBGL(0, tex, 0, 0, 0);
   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION);
 
   debug("\nIf 'texture' was generated by a different WebGL2RenderingContext than this one, " +
@@ -220,7 +224,7 @@
   const tex2 = gl2.createTexture();
   gl2.bindTexture(gl2.TEXTURE_2D, tex2);
   gl2.texStorage2D(gl2.TEXTURE_2D, 1, gl2.RGBA8, 1, 1);
-  pls.framebufferTexturePixelLocalStorageWEBGL(0, tex2, 0, 0);
+  pls.framebufferTexturePixelLocalStorageWEBGL(0, tex2, 0, 0, 0);
   wtu.glErrorShouldBe(gl2, gl2.NONE);
   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION);
 
@@ -294,10 +298,10 @@
   gl.bindTexture(gl.TEXTURE_2D, validTex);
   gl.texStorage2D(gl.TEXTURE_2D, 1, gl.RGBA8, 1, 1);
   wtu.glErrorShouldBe(gl, gl.NONE);
-  pls.framebufferTexturePixelLocalStorageWEBGL(0, validTex, 0, 0);
+  pls.framebufferTexturePixelLocalStorageWEBGL(0, validTex, 0, 0, 0);
   shouldBeTrue(`pls.getFramebufferPixelLocalStorageParameterWEBGL(
                     0, pls.PIXEL_LOCAL_TEXTURE_NAME_WEBGL) === validTex`);
-  pls.framebufferTexturePixelLocalStorageWEBGL(0, null, 0, 0);
+  pls.framebufferTexturePixelLocalStorageWEBGL(0, null, 0, 0, 0);
   shouldBeTrue(`pls.getFramebufferPixelLocalStorageParameterWEBGL(
                     0, pls.PIXEL_LOCAL_TEXTURE_NAME_WEBGL) === null`);
 
@@ -323,7 +327,7 @@
 
   const plsFBO = localGL.createFramebuffer();
   localGL.bindFramebuffer(localGL.FRAMEBUFFER, plsFBO);
-  localPLS.framebufferTexturePixelLocalStorageWEBGL(0, tex, 0, 0);
+  localPLS.framebufferTexturePixelLocalStorageWEBGL(0, tex, 0, 0, 0);
   wtu.glErrorShouldBe(localGL, localGL.NONE);
 
   localGL.viewport(0, 0, localCanvas.width, localCanvas.height);