diff --git a/lib/client-rect-observer.ts b/lib/client-rect-observer.ts
index 9926950..0b445ab 100644
--- a/lib/client-rect-observer.ts
+++ b/lib/client-rect-observer.ts
@@ -191,55 +191,3 @@ export class ClientRectObserver {
     }
   }
 }
-
-export type ClientRectObserverEntryCallback = (entry: ClientRectObserverEntry) => void;
-
-export class ClientRectObserverManager {
-  static #instance: ClientRectObserverManager | null = null;
-
-  // singleton so we only observe elements once
-  constructor() {
-    if (ClientRectObserverManager.#instance === null) {
-      ClientRectObserverManager.#instance = this;
-    }
-    return ClientRectObserverManager.#instance;
-  }
-
-  #elementMap = new WeakMap<Element, Set<ClientRectObserverEntryCallback>>();
-
-  #vo = new ClientRectObserver((entries) => {
-    for (const entry of entries) {
-      const callbacks = this.#elementMap.get(entry.target);
-
-      if (callbacks) {
-        callbacks.forEach((callback) => callback(entry));
-      }
-    }
-  });
-
-  observe(target: Element, callback: ClientRectObserverEntryCallback): void {
-    let callbacks = this.#elementMap.get(target);
-
-    if (callbacks === undefined) {
-      this.#vo.observe(target);
-      this.#elementMap.set(target, (callbacks = new Set()));
-    } else {
-      callback({ target, contentRect: target.getBoundingClientRect() });
-    }
-
-    callbacks.add(callback);
-  }
-
-  unobserve(target: Element, callback: ClientRectObserverEntryCallback): void {
-    let callbacks = this.#elementMap.get(target);
-
-    if (callbacks === undefined) return;
-
-    callbacks.delete(callback);
-
-    if (callbacks.size === 0) {
-      this.#vo.unobserve(target);
-      this.#elementMap.delete(target);
-    }
-  }
-}