diff --git a/packages/viewer/src/components/viewer/index.tsx b/packages/viewer/src/components/viewer/index.tsx
index ada0067e..eca2c561 100644
--- a/packages/viewer/src/components/viewer/index.tsx
+++ b/packages/viewer/src/components/viewer/index.tsx
@@ -1,5 +1,9 @@
 'use client'
 
+// Must run before @react-three/fiber's Canvas instantiates new THREE.Clock().
+// See lib/suppress-three-clock-warning.ts for rationale and removal condition.
+import '../../lib/suppress-three-clock-warning'
+
 import {
   CeilingSystem,
   DoorSystem,
diff --git a/packages/viewer/src/lib/suppress-three-clock-warning.ts b/packages/viewer/src/lib/suppress-three-clock-warning.ts
new file mode 100644
index 00000000..d1892f2e
--- /dev/null
+++ b/packages/viewer/src/lib/suppress-three-clock-warning.ts
@@ -0,0 +1,63 @@
+/**
+ * Suppresses the `THREE.Clock: This module has been deprecated` warning
+ * emitted by three.js r183+ on every `new THREE.Clock()` call.
+ *
+ * We don't instantiate `Clock` ourselves — `@react-three/fiber` 9.x
+ * (current stable) creates one internally per `<Canvas>` mount. The
+ * migration to `THREE.Timer` lands in R3F 10.x (still alpha).
+ *
+ * Uses three's `setConsoleFunction` hook so we don't touch `console.warn`
+ * globally. Only the exact Clock deprecation message is suppressed; all
+ * other three.js logs (including TSL stack-trace warnings) pass through
+ * untouched.
+ *
+ * Runs in production as well as dev — the suppressed message is a pure
+ * deprecation notice with no user-actionable content.
+ *
+ * REMOVAL: safe to delete once `@react-three/fiber` no longer constructs
+ * `new THREE.Clock()`. To verify after an R3F upgrade:
+ *   grep -n "new THREE.Clock" node_modules/@react-three/fiber/dist/*.js
+ * No hits → delete this file and its import in components/viewer/index.tsx.
+ *
+ * @see https://github.com/pascalorg/editor/issues/213
+ */
+
+import { setConsoleFunction } from 'three'
+
+// three's warn() prepends 'THREE.' to its first argument, and the Clock
+// constructor passes 'THREE.Clock: ...', producing a double-prefixed
+// string. Exact equality keeps the suppression surgical — if three ever
+// rewords this, the filter stops matching and the message resurfaces.
+const CLOCK_DEPRECATION_MESSAGE =
+  'THREE.THREE.Clock: This module has been deprecated. Please use THREE.Timer instead.'
+
+type ConsoleMethod = 'log' | 'warn' | 'error'
+
+// HMR-idempotent install guard. setConsoleFunction is a single-slot global
+// in three, so re-evaluating this module on HMR would reinstall the hook.
+const INSTALLED = Symbol.for('@pascal-app/viewer/suppress-three-clock-warning')
+type GlobalWithFlag = typeof globalThis & { [INSTALLED]?: true }
+
+if (!(globalThis as GlobalWithFlag)[INSTALLED]) {
+  ;(globalThis as GlobalWithFlag)[INSTALLED] = true
+
+  setConsoleFunction((method: ConsoleMethod, message: string, ...params: unknown[]) => {
+    if (method === 'warn' && message === CLOCK_DEPRECATION_MESSAGE) {
+      return
+    }
+
+    // Mirror three's default stack-trace handling so TSL warnings/errors
+    // keep their clickable stack frames.
+    if (method !== 'log') {
+      const first = params[0] as
+        | { isStackTrace?: boolean; getError?: (m: string) => Error }
+        | undefined
+      if (first?.isStackTrace && typeof first.getError === 'function') {
+        console[method](first.getError(message))
+        return
+      }
+    }
+
+    console[method](message, ...params)
+  })
+}