diff --git a/resources/chromium/webxr-test.js b/resources/chromium/webxr-test.js
index 61dde7981d2b5b..40bc915f4477ee 100644
--- a/resources/chromium/webxr-test.js
+++ b/resources/chromium/webxr-test.js
@@ -336,7 +336,6 @@ class MockRuntime {
     'secondary-views': xrSessionMojom.XRSessionFeature.SECONDARY_VIEWS,
     'camera-access': xrSessionMojom.XRSessionFeature.CAMERA_ACCESS,
     'layers': xrSessionMojom.XRSessionFeature.LAYERS,
-    'plane-detection': xrSessionMojom.XRSessionFeature.PLANE_DETECTION,
   };
 
   static _sessionModeToMojoMap = {
@@ -372,19 +371,6 @@ class MockRuntime {
     "unsigned-short": xrSessionMojom.XRDepthDataFormat.kUnsignedShort,
   };
 
-  static _semanticLabelToMojoMap = {
-    "other": vrMojom.XRSemanticLabel.kOther,
-    "floor": vrMojom.XRSemanticLabel.kFloor,
-    "wall": vrMojom.XRSemanticLabel.kWall,
-    "ceiling": vrMojom.XRSemanticLabel.kCeiling,
-    "table": vrMojom.XRSemanticLabel.kTable,
-  };
-
-  static _planeOrientationToMojoMap = {
-    "horizontal": vrMojom.XRPlaneOrientation.HORIZONTAL,
-    "vertical": vrMojom.XRPlaneOrientation.VERTICAL,
-  };
-
 
   constructor(fakeDeviceInit, service) {
     this.sessionClient_ = null;
@@ -412,9 +398,6 @@ class MockRuntime {
     // ID of the next subscription to be assigned.
     this.next_hit_test_id_ = 1n;
 
-    this.world_ = null;
-    this.worldDirty_ = false;
-
     this.anchor_controllers_ = new Map();
     // ID of the next anchor to be assigned.
     this.next_anchor_id_ = 1n;
@@ -616,12 +599,10 @@ class MockRuntime {
   // WebXR Test API Hit Test extensions
   setWorld(world) {
     this.world_ = world;
-    this.worldDirty_ = true;
   }
 
   clearWorld() {
     this.world_ = null;
-    this.worldDirty_ = true;
   }
 
   // WebXR Test API Anchor extensions
@@ -1049,8 +1030,6 @@ class MockRuntime {
 
         this._calculateAnchorInformation(frameData);
 
-        this._calculatePlaneInformation(frameData);
-
         if (options.depthActive) {
           this._calculateDepthInformation(frameData);
         }
@@ -1431,65 +1410,6 @@ class MockRuntime {
     }
   }
 
-  // Private functions - plane detection implementation:
-
-  // Modifies passed in frameData to add plane detection results.
-  _calculatePlaneInformation(frameData) {
-    if (!this.enabledFeatures_.includes(xrSessionMojom.XRSessionFeature.PLANE_DETECTION)) {
-      return;
-    }
-
-    frameData.detectedPlanesData = {
-      allPlanesIds: [],
-      updatedPlanesData: []
-    };
-
-    if (!this.world_) {
-      this.worldDirty_ = false;
-      return;
-    }
-
-    for (let i = 0; i < this.world_.hitTestRegions.length; i++) {
-      const region = this.world_.hitTestRegions[i];
-      if (region.type !== "plane") {
-        continue;
-      }
-
-      // PlaneId is just an idValue (uint64). We can use the index in the hitTestRegions.
-      // Though 0 is an invalid id, so increment by 1.
-      const planeId = { idValue: BigInt(i + 1) };
-      frameData.detectedPlanesData.allPlanesIds.push(planeId);
-
-      // Only treat planes as updated if the world state was changed since last frame.
-      if (this.worldDirty_) {
-        const planeInfo = region.planeInfo;
-        if (planeInfo) {
-          let semanticLabel = null;
-          if (planeInfo.semanticLabel && planeInfo.semanticLabel in MockRuntime._semanticLabelToMojoMap) {
-            semanticLabel = MockRuntime._semanticLabelToMojoMap[planeInfo.semanticLabel];
-          }
-          const planeData = {
-            id: planeId,
-            orientation: MockRuntime._planeOrientationToMojoMap[planeInfo.orientation],
-            mojoFromPlane: getPoseFromTransform(planeInfo.origin),
-            semanticLabel: semanticLabel,
-            polygon: []
-          };
-
-          if (planeInfo.polygon) {
-            for (const point of planeInfo.polygon) {
-              planeData.polygon.push({ x: point.x, z: point.z });
-            }
-          }
-
-          frameData.detectedPlanesData.updatedPlanesData.push(planeData);
-        }
-      }
-    }
-
-    this.worldDirty_ = false;
-  }
-
   // Private functions - depth sensing implementation:
 
   /**
diff --git a/webxr/plane-detection/xrFrame_detectedPlanes_inactive_frame.https.html b/webxr/plane-detection/xrFrame_detectedPlanes_inactive_frame.https.html
deleted file mode 100644
index 21c0b3c8b50cff..00000000000000
--- a/webxr/plane-detection/xrFrame_detectedPlanes_inactive_frame.https.html
+++ /dev/null
@@ -1,35 +0,0 @@
-<!DOCTYPE html>
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="../resources/webxr_util.js"></script>
-<script src="../resources/webxr_test_constants.js"></script>
-
-<script>
-let testName = "Accessing detectedPlanes on inactive frame throws InvalidStateError";
-
-xr_session_promise_test(
-  testName,
-  (session, controller, t) => {
-    return new Promise((resolve) => {
-      session.requestAnimationFrame((time, frame) => {
-        // Access during rAF is fine.
-        let planes = frame.detectedPlanes;
-
-        // The frame is only active during the requestAnimationFrame callback.
-        // We use step_timeout to queue a task that runs after this callback
-        // has completed and the frame has become inactive.
-        t.step_timeout(() => {
-          t.step(() => {
-            assert_throws_dom("InvalidStateError", () => frame.detectedPlanes);
-          });
-          resolve();
-        }, 0);
-      });
-    });
-  },
-  IMMERSIVE_AR_DEVICE,
-  "immersive-ar",
-  { requiredFeatures: ["plane-detection"] }
-);
-
-</script>
diff --git a/webxr/plane-detection/xrFrame_detectedPlanes_plumbing.https.html b/webxr/plane-detection/xrFrame_detectedPlanes_plumbing.https.html
deleted file mode 100644
index 4ac2cbc384dfa2..00000000000000
--- a/webxr/plane-detection/xrFrame_detectedPlanes_plumbing.https.html
+++ /dev/null
@@ -1,70 +0,0 @@
-<!DOCTYPE html>
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="../resources/webxr_util.js"></script>
-<script src="../resources/webxr_test_constants.js"></script>
-<script src="../resources/webxr_test_asserts.js"></script>
-
-<script>
-let testName = "XRFrame.detectedPlanes plumbing works";
-
-xr_session_promise_test(
-  testName,
-  (session, controller, t) => {
-    controller.setWorld({
-      hitTestRegions: [
-        DEFAULT_FLOOR_PLANE,
-        {
-          type: "plane",
-          faces: [
-            { vertices: [{x: -1, y: 1, z: -5}, {x: 1, y: 1, z: -5}, {x: 1, y: 2, z: -5}] }
-          ],
-          planeInfo: {
-            orientation: "vertical",
-            origin: { position: [0, 1.5, -5], orientation: [0, 0, 0, 1] },
-            polygon: [
-              {x: -1, z: -0.5},
-              {x: 1, z: -0.5},
-              {x: 0, z: 0.5}
-            ],
-            semanticLabel: "wall"
-          }
-        }
-      ]
-    });
-
-    return new Promise((resolve) => {
-      session.requestAnimationFrame((time, frame) => {
-        t.step(() => {
-          let planes = frame.detectedPlanes;
-          assert_not_equals(planes, null, "detectedPlanes should not be null");
-          assert_equals(planes.size, 2, "Should detect 2 planes");
-
-          let planeList = [];
-          planes.forEach(p => planeList.push(p));
-
-          // Sort planes by orientation to identify them reliably
-          planeList.sort((a, b) => (a.orientation > b.orientation) ? 1 : -1);
-
-          let horizontalPlane = planeList[0]; // "horizontal"
-          let verticalPlane = planeList[1];   // "vertical"
-
-          assert_equals(horizontalPlane.orientation, "horizontal");
-          assert_equals(horizontalPlane.semanticLabel, "floor");
-          assert_equals(horizontalPlane.polygon.length, 4);
-
-          assert_equals(verticalPlane.orientation, "vertical");
-          assert_equals(verticalPlane.semanticLabel, "wall");
-          assert_equals(verticalPlane.polygon.length, 3);
-        });
-
-        resolve();
-      });
-    });
-  },
-  IMMERSIVE_AR_DEVICE,
-  "immersive-ar",
-  { requiredFeatures: ["plane-detection"] }
-);
-
-</script>
diff --git a/webxr/plane-detection/xrPlane_identity.https.html b/webxr/plane-detection/xrPlane_identity.https.html
deleted file mode 100644
index b4188219627224..00000000000000
--- a/webxr/plane-detection/xrPlane_identity.https.html
+++ /dev/null
@@ -1,48 +0,0 @@
-<!DOCTYPE html>
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="../resources/webxr_util.js"></script>
-<script src="../resources/webxr_test_constants.js"></script>
-
-<script>
-let testName = "XRPlane objects are the same across frames";
-
-xr_session_promise_test(
-  testName,
-  (session, controller, t) => {
-    controller.setWorld(DEFAULT_WORLD_WITH_FLOOR);
-
-    let firstFramePlane = null;
-
-    return new Promise((resolve) => {
-      session.requestAnimationFrame((time, frame) => {
-        t.step(() => {
-          let planes = frame.detectedPlanes;
-          assert_equals(planes.size, 1);
-          // XRPlaneSet is set-like, we use forEach to get the first/only plane.
-          planes.forEach(p => { firstFramePlane = p; });
-          assert_not_equals(firstFramePlane, null);
-        });
-
-        session.requestAnimationFrame((time, frame) => {
-          t.step(() => {
-            let secondFramePlanes = frame.detectedPlanes;
-            assert_equals(secondFramePlanes.size, 1);
-            let secondFramePlane = null;
-          // XRPlaneSet is set-like, we use forEach to get the first/only plane.
-            secondFramePlanes.forEach(p => { secondFramePlane = p; });
-
-            assert_equals(firstFramePlane, secondFramePlane, "XRPlane objects should be identical across frames");
-          });
-
-          resolve();
-        });
-      });
-    });
-  },
-  IMMERSIVE_AR_DEVICE,
-  "immersive-ar",
-  { requiredFeatures: ["plane-detection"] }
-);
-
-</script>
diff --git a/webxr/plane-detection/xrPlane_lastChangedTime_no_change.https.html b/webxr/plane-detection/xrPlane_lastChangedTime_no_change.https.html
deleted file mode 100644
index 21f193a89ee962..00000000000000
--- a/webxr/plane-detection/xrPlane_lastChangedTime_no_change.https.html
+++ /dev/null
@@ -1,60 +0,0 @@
-<!DOCTYPE html>
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="../resources/webxr_util.js"></script>
-<script src="../resources/webxr_test_constants.js"></script>
-
-<script>
-let testName = "XRPlane.lastChangedTime does not update if plane does not change";
-
-xr_session_promise_test(
-  testName,
-  (session, controller, t) => {
-    controller.setWorld(DEFAULT_WORLD_WITH_FLOOR);
-
-    let firstFrameTime = null;
-
-    return new Promise((resolve) => {
-      session.requestAnimationFrame((time, frame) => {
-        t.step(() => {
-          let planes = frame.detectedPlanes;
-          assert_equals(planes.size, 1);
-          // XRPlaneSet is set-like, we use forEach to get the first/only plane.
-          planes.forEach(p => { firstFrameTime = p.lastChangedTime; });
-        });
-
-        // Request next frame without updating the world.
-        session.requestAnimationFrame((time, frame) => {
-          t.step(() => {
-            let secondFramePlanes = frame.detectedPlanes;
-            assert_equals(secondFramePlanes.size, 1);
-            let secondFrameTime = null;
-          // XRPlaneSet is set-like, we use forEach to get the first/only plane.
-            secondFramePlanes.forEach(p => { secondFrameTime = p.lastChangedTime; });
-            assert_equals(secondFrameTime, firstFrameTime, "lastChangedTime should not change");
-          });
-
-          // Now update world and verify it changes.
-          controller.setWorld(DEFAULT_WORLD_WITH_FLOOR);
-          session.requestAnimationFrame((time, frame) => {
-            t.step(() => {
-              let thirdFramePlanes = frame.detectedPlanes;
-              assert_equals(thirdFramePlanes.size, 1);
-              let thirdFrameTime = null;
-          // XRPlaneSet is set-like, we use forEach to get the first/only plane.
-              thirdFramePlanes.forEach(p => { thirdFrameTime = p.lastChangedTime; });
-              assert_greater_than(thirdFrameTime, firstFrameTime, "lastChangedTime should update after setWorld");
-            });
-
-            resolve();
-          });
-        });
-      });
-    });
-  },
-  IMMERSIVE_AR_DEVICE,
-  "immersive-ar",
-  { requiredFeatures: ["plane-detection"] }
-);
-
-</script>
diff --git a/webxr/plane-detection/xrSession_initiateRoomCapture.https.html b/webxr/plane-detection/xrSession_initiateRoomCapture.https.html
deleted file mode 100644
index 351b15f92125ae..00000000000000
--- a/webxr/plane-detection/xrSession_initiateRoomCapture.https.html
+++ /dev/null
@@ -1,43 +0,0 @@
-<!DOCTYPE html>
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="../resources/webxr_util.js"></script>
-<script src="../resources/webxr_test_constants.js"></script>
-
-<script>
-xr_session_promise_test(
-  "initiateRoomCapture behavior",
-  async (session, controller, t) => {
-    // 1. Successful call
-    await session.initiateRoomCapture();
-
-    // 2. Calling it a second time should throw InvalidStateError
-    await promise_rejects_dom(t, "InvalidStateError", session.initiateRoomCapture());
-  },
-  IMMERSIVE_AR_DEVICE,
-  "immersive-ar",
-  { requiredFeatures: ["plane-detection"] }
-);
-
-xr_session_promise_test(
-  "initiateRoomCapture throws NotSupportedError if feature not requested",
-  async (session, controller, t) => {
-    await promise_rejects_dom(t, "NotSupportedError", session.initiateRoomCapture());
-  },
-  IMMERSIVE_AR_DEVICE,
-  "immersive-ar",
-  { requiredFeatures: [] }
-);
-
-xr_session_promise_test(
-  "initiateRoomCapture throws InvalidStateError if session ended",
-  async (session, controller, t) => {
-    await session.end();
-    await promise_rejects_dom(t, "InvalidStateError", session.initiateRoomCapture());
-  },
-  IMMERSIVE_AR_DEVICE,
-  "immersive-ar",
-  { requiredFeatures: ["plane-detection"] }
-);
-
-</script>
\ No newline at end of file
diff --git a/webxr/resources/webxr_test_constants.js b/webxr/resources/webxr_test_constants.js
index 79b7d028f12cc4..c08cdd9b251750 100644
--- a/webxr/resources/webxr_test_constants.js
+++ b/webxr/resources/webxr_test_constants.js
@@ -163,33 +163,9 @@ const ALL_FEATURES = [
   'depth-sensing',
   'secondary-views',
   'camera-access',
-  'layers',
-  'plane-detection'
+  'layers'
 ];
 
-const DEFAULT_FLOOR_PLANE = {
-  type: "plane",
-  faces: [
-    { vertices: [{x: -1, y: 0, z: -1}, {x: 1, y: 0, z: -1}, {x: 1, y: 0, z: 1}] },
-    { vertices: [{x: -1, y: 0, z: -1}, {x: 1, y: 0, z: 1}, {x: -1, y: 0, z: 1}] }
-  ],
-  planeInfo: {
-    orientation: "horizontal",
-    origin: { position: [0, 0, 0], orientation: [0, 0, 0, 1] },
-    polygon: [
-      {x: -1, z: -1},
-      {x: 1, z: -1},
-      {x: 1, z: 1},
-      {x: -1, z: 1}
-    ],
-    semanticLabel: "floor"
-  }
-};
-
-const DEFAULT_WORLD_WITH_FLOOR = {
-  hitTestRegions: [ DEFAULT_FLOOR_PLANE ]
-};
-
 const TRACKED_IMMERSIVE_DEVICE = {
     supportsImmersive: true,
     supportedModes: [ "inline", "immersive-vr"],