diff --git a/apps/browser/src/autofill/content/autofill-init.spec.ts b/apps/browser/src/autofill/content/autofill-init.spec.ts
index d612e63f82c..eef7fe32dd0 100644
--- a/apps/browser/src/autofill/content/autofill-init.spec.ts
+++ b/apps/browser/src/autofill/content/autofill-init.spec.ts
@@ -347,6 +347,18 @@ describe("AutofillInit", () => {
       );
     });
 
+    it("removes the LOAD event listener", () => {
+      jest.spyOn(window, "removeEventListener");
+
+      autofillInit.init();
+      autofillInit.destroy();
+
+      expect(window.removeEventListener).toHaveBeenCalledWith(
+        "load",
+        autofillInit["sendCollectDetailsMessage"],
+      );
+    });
+
     it("removes the extension message listeners", () => {
       autofillInit.destroy();
 
diff --git a/apps/browser/src/autofill/overlay/inline-menu/content/autofill-inline-menu-content.service.spec.ts b/apps/browser/src/autofill/overlay/inline-menu/content/autofill-inline-menu-content.service.spec.ts
index b7bd24c537b..00c214c32e7 100644
--- a/apps/browser/src/autofill/overlay/inline-menu/content/autofill-inline-menu-content.service.spec.ts
+++ b/apps/browser/src/autofill/overlay/inline-menu/content/autofill-inline-menu-content.service.spec.ts
@@ -645,6 +645,292 @@ describe("AutofillInlineMenuContentService", () => {
 
       expect(disconnectSpy).toHaveBeenCalled();
     });
+
+    it("unobserves custom elements", () => {
+      const disconnectSpy = jest.spyOn(
+        autofillInlineMenuContentService["inlineMenuElementsMutationObserver"],
+        "disconnect",
+      );
+
+      autofillInlineMenuContentService.destroy();
+
+      expect(disconnectSpy).toHaveBeenCalled();
+    });
+
+    it("unobserves the container element", () => {
+      const disconnectSpy = jest.spyOn(
+        autofillInlineMenuContentService["containerElementMutationObserver"],
+        "disconnect",
+      );
+
+      autofillInlineMenuContentService.destroy();
+
+      expect(disconnectSpy).toHaveBeenCalled();
+    });
+
+    it("clears the mutation observer iterations reset timeout", () => {
+      jest.useFakeTimers();
+      const clearTimeoutSpy = jest.spyOn(globalThis, "clearTimeout");
+      autofillInlineMenuContentService["mutationObserverIterationsResetTimeout"] = setTimeout(
+        jest.fn(),
+        1000,
+      );
+
+      autofillInlineMenuContentService.destroy();
+
+      expect(clearTimeoutSpy).toHaveBeenCalled();
+      expect(autofillInlineMenuContentService["mutationObserverIterationsResetTimeout"]).toBeNull();
+    });
+
+    it("destroys the button iframe", () => {
+      const mockButtonIframe = { destroy: jest.fn() };
+      autofillInlineMenuContentService["buttonIframe"] = mockButtonIframe as any;
+
+      autofillInlineMenuContentService.destroy();
+
+      expect(mockButtonIframe.destroy).toHaveBeenCalled();
+    });
+
+    it("destroys the list iframe", () => {
+      const mockListIframe = { destroy: jest.fn() };
+      autofillInlineMenuContentService["listIframe"] = mockListIframe as any;
+
+      autofillInlineMenuContentService.destroy();
+
+      expect(mockListIframe.destroy).toHaveBeenCalled();
+    });
+  });
+
+  describe("observeCustomElements", () => {
+    it("observes the button element for attribute mutations", () => {
+      const buttonElement = document.createElement("div");
+      autofillInlineMenuContentService["buttonElement"] = buttonElement;
+      const observeSpy = jest.spyOn(
+        autofillInlineMenuContentService["inlineMenuElementsMutationObserver"],
+        "observe",
+      );
+
+      autofillInlineMenuContentService["observeCustomElements"]();
+
+      expect(observeSpy).toHaveBeenCalledWith(buttonElement, { attributes: true });
+    });
+
+    it("observes the list element for attribute mutations", () => {
+      const listElement = document.createElement("div");
+      autofillInlineMenuContentService["listElement"] = listElement;
+      const observeSpy = jest.spyOn(
+        autofillInlineMenuContentService["inlineMenuElementsMutationObserver"],
+        "observe",
+      );
+
+      autofillInlineMenuContentService["observeCustomElements"]();
+
+      expect(observeSpy).toHaveBeenCalledWith(listElement, { attributes: true });
+    });
+
+    it("does not observe when no elements exist", () => {
+      autofillInlineMenuContentService["buttonElement"] = undefined;
+      autofillInlineMenuContentService["listElement"] = undefined;
+      const observeSpy = jest.spyOn(
+        autofillInlineMenuContentService["inlineMenuElementsMutationObserver"],
+        "observe",
+      );
+
+      autofillInlineMenuContentService["observeCustomElements"]();
+
+      expect(observeSpy).not.toHaveBeenCalled();
+    });
+  });
+
+  describe("observeContainerElement", () => {
+    it("observes the container element for child list mutations", () => {
+      const containerElement = document.createElement("div");
+      const observeSpy = jest.spyOn(
+        autofillInlineMenuContentService["containerElementMutationObserver"],
+        "observe",
+      );
+
+      autofillInlineMenuContentService["observeContainerElement"](containerElement);
+
+      expect(observeSpy).toHaveBeenCalledWith(containerElement, { childList: true });
+    });
+  });
+
+  describe("unobserveContainerElement", () => {
+    it("disconnects the container element mutation observer", () => {
+      const disconnectSpy = jest.spyOn(
+        autofillInlineMenuContentService["containerElementMutationObserver"],
+        "disconnect",
+      );
+
+      autofillInlineMenuContentService["unobserveContainerElement"]();
+
+      expect(disconnectSpy).toHaveBeenCalled();
+    });
+
+    it("handles the case when the mutation observer is undefined", () => {
+      autofillInlineMenuContentService["containerElementMutationObserver"] = undefined as any;
+
+      expect(() => autofillInlineMenuContentService["unobserveContainerElement"]()).not.toThrow();
+    });
+  });
+
+  describe("observePageAttributes", () => {
+    it("observes the document element for attribute mutations", () => {
+      const observeSpy = jest.spyOn(
+        autofillInlineMenuContentService["htmlMutationObserver"],
+        "observe",
+      );
+
+      autofillInlineMenuContentService["observePageAttributes"]();
+
+      expect(observeSpy).toHaveBeenCalledWith(document.documentElement, { attributes: true });
+    });
+
+    it("observes the body element for attribute mutations", () => {
+      const observeSpy = jest.spyOn(
+        autofillInlineMenuContentService["bodyMutationObserver"],
+        "observe",
+      );
+
+      autofillInlineMenuContentService["observePageAttributes"]();
+
+      expect(observeSpy).toHaveBeenCalledWith(document.body, { attributes: true });
+    });
+  });
+
+  describe("unobservePageAttributes", () => {
+    it("disconnects the html mutation observer", () => {
+      const disconnectSpy = jest.spyOn(
+        autofillInlineMenuContentService["htmlMutationObserver"],
+        "disconnect",
+      );
+
+      autofillInlineMenuContentService["unobservePageAttributes"]();
+
+      expect(disconnectSpy).toHaveBeenCalled();
+    });
+
+    it("disconnects the body mutation observer", () => {
+      const disconnectSpy = jest.spyOn(
+        autofillInlineMenuContentService["bodyMutationObserver"],
+        "disconnect",
+      );
+
+      autofillInlineMenuContentService["unobservePageAttributes"]();
+
+      expect(disconnectSpy).toHaveBeenCalled();
+    });
+  });
+
+  describe("checkPageRisks", () => {
+    it("returns true and closes inline menu when page is not opaque", async () => {
+      jest.spyOn(autofillInlineMenuContentService as any, "getPageIsOpaque").mockReturnValue(false);
+      const closeInlineMenuSpy = jest.spyOn(
+        autofillInlineMenuContentService as any,
+        "closeInlineMenu",
+      );
+
+      const result = await autofillInlineMenuContentService["checkPageRisks"]();
+
+      expect(result).toBe(true);
+      expect(closeInlineMenuSpy).toHaveBeenCalled();
+    });
+
+    it("returns true and closes inline menu when inline menu is disabled", async () => {
+      jest.spyOn(autofillInlineMenuContentService as any, "getPageIsOpaque").mockReturnValue(true);
+      autofillInlineMenuContentService["inlineMenuEnabled"] = false;
+      const closeInlineMenuSpy = jest.spyOn(
+        autofillInlineMenuContentService as any,
+        "closeInlineMenu",
+      );
+
+      const result = await autofillInlineMenuContentService["checkPageRisks"]();
+
+      expect(result).toBe(true);
+      expect(closeInlineMenuSpy).toHaveBeenCalled();
+    });
+
+    it("returns false when page is opaque and inline menu is enabled", async () => {
+      jest.spyOn(autofillInlineMenuContentService as any, "getPageIsOpaque").mockReturnValue(true);
+      autofillInlineMenuContentService["inlineMenuEnabled"] = true;
+      const closeInlineMenuSpy = jest.spyOn(
+        autofillInlineMenuContentService as any,
+        "closeInlineMenu",
+      );
+
+      const result = await autofillInlineMenuContentService["checkPageRisks"]();
+
+      expect(result).toBe(false);
+      expect(closeInlineMenuSpy).not.toHaveBeenCalled();
+    });
+  });
+
+  describe("handlePageMutations", () => {
+    it("checks page risks when mutations include attribute changes", async () => {
+      const checkPageRisksSpy = jest.spyOn(
+        autofillInlineMenuContentService as any,
+        "checkPageRisks",
+      );
+      const mutations = [{ type: "attributes" } as MutationRecord];
+
+      await autofillInlineMenuContentService["handlePageMutations"](mutations);
+
+      expect(checkPageRisksSpy).toHaveBeenCalled();
+    });
+
+    it("does not check page risks when mutations do not include attribute changes", async () => {
+      const checkPageRisksSpy = jest.spyOn(
+        autofillInlineMenuContentService as any,
+        "checkPageRisks",
+      );
+      const mutations = [{ type: "childList" } as MutationRecord];
+
+      await autofillInlineMenuContentService["handlePageMutations"](mutations);
+
+      expect(checkPageRisksSpy).not.toHaveBeenCalled();
+    });
+  });
+
+  describe("clearPersistentLastChildOverrideTimeout", () => {
+    it("clears the timeout when it exists", () => {
+      jest.useFakeTimers();
+      const clearTimeoutSpy = jest.spyOn(globalThis, "clearTimeout");
+      autofillInlineMenuContentService["handlePersistentLastChildOverrideTimeout"] = setTimeout(
+        jest.fn(),
+        1000,
+      );
+
+      autofillInlineMenuContentService["clearPersistentLastChildOverrideTimeout"]();
+
+      expect(clearTimeoutSpy).toHaveBeenCalled();
+    });
+
+    it("does nothing when the timeout is null", () => {
+      const clearTimeoutSpy = jest.spyOn(globalThis, "clearTimeout");
+      autofillInlineMenuContentService["handlePersistentLastChildOverrideTimeout"] = null;
+
+      autofillInlineMenuContentService["clearPersistentLastChildOverrideTimeout"]();
+
+      expect(clearTimeoutSpy).not.toHaveBeenCalled();
+    });
+  });
+
+  describe("elementAtCenterOfInlineMenuPosition", () => {
+    it("returns the element at the center of the given position", () => {
+      const mockElement = document.createElement("div");
+      jest.spyOn(globalThis.document, "elementFromPoint").mockReturnValue(mockElement);
+
+      const result = autofillInlineMenuContentService["elementAtCenterOfInlineMenuPosition"]({
+        top: 100,
+        left: 200,
+        width: 50,
+        height: 30,
+      });
+
+      expect(globalThis.document.elementFromPoint).toHaveBeenCalledWith(225, 115);
+      expect(result).toBe(mockElement);
+    });
   });
 
   describe("getOwnedTagNames", () => {
@@ -975,6 +1261,25 @@ describe("AutofillInlineMenuContentService", () => {
     });
   });
 
+  describe("unobserveCustomElements", () => {
+    it("disconnects the inline menu elements mutation observer", () => {
+      const disconnectSpy = jest.spyOn(
+        autofillInlineMenuContentService["inlineMenuElementsMutationObserver"],
+        "disconnect",
+      );
+
+      autofillInlineMenuContentService["unobserveCustomElements"]();
+
+      expect(disconnectSpy).toHaveBeenCalled();
+    });
+
+    it("handles the case when the mutation observer is undefined", () => {
+      autofillInlineMenuContentService["inlineMenuElementsMutationObserver"] = undefined as any;
+
+      expect(() => autofillInlineMenuContentService["unobserveCustomElements"]()).not.toThrow();
+    });
+  });
+
   describe("getPageIsOpaque", () => {
     it("returns false when no page elements exist", () => {
       jest.spyOn(globalThis.document, "querySelectorAll").mockReturnValue([] as any);
diff --git a/apps/browser/src/autofill/overlay/inline-menu/iframe-content/autofill-inline-menu-iframe.service.spec.ts b/apps/browser/src/autofill/overlay/inline-menu/iframe-content/autofill-inline-menu-iframe.service.spec.ts
index f1ed6875f90..5e9d7c1da48 100644
--- a/apps/browser/src/autofill/overlay/inline-menu/iframe-content/autofill-inline-menu-iframe.service.spec.ts
+++ b/apps/browser/src/autofill/overlay/inline-menu/iframe-content/autofill-inline-menu-iframe.service.spec.ts
@@ -752,4 +752,164 @@ describe("AutofillInlineMenuIframeService", () => {
       expect(autofillInlineMenuIframeService["iframe"].title).toBe("title");
     });
   });
+
+  describe("destroy", () => {
+    beforeEach(() => {
+      autofillInlineMenuIframeService.initMenuIframe();
+      autofillInlineMenuIframeService["iframe"].dispatchEvent(new Event(EVENTS.LOAD));
+      portSpy = autofillInlineMenuIframeService["port"];
+    });
+
+    it("removes the LOAD event listener from the iframe", () => {
+      const removeEventListenerSpy = jest.spyOn(
+        autofillInlineMenuIframeService["iframe"],
+        "removeEventListener",
+      );
+
+      autofillInlineMenuIframeService.destroy();
+
+      expect(removeEventListenerSpy).toHaveBeenCalledWith(
+        EVENTS.LOAD,
+        autofillInlineMenuIframeService["setupPortMessageListener"],
+      );
+    });
+
+    it("clears the aria alert timeout", () => {
+      jest.spyOn(autofillInlineMenuIframeService, "clearAriaAlert");
+      autofillInlineMenuIframeService["ariaAlertTimeout"] = setTimeout(jest.fn(), 1000);
+
+      autofillInlineMenuIframeService.destroy();
+
+      expect(autofillInlineMenuIframeService.clearAriaAlert).toHaveBeenCalled();
+    });
+
+    it("clears the fade in timeout", () => {
+      jest.useFakeTimers();
+      jest.spyOn(globalThis, "clearTimeout");
+      autofillInlineMenuIframeService["fadeInTimeout"] = setTimeout(jest.fn(), 1000);
+
+      autofillInlineMenuIframeService.destroy();
+
+      expect(globalThis.clearTimeout).toHaveBeenCalled();
+      expect(autofillInlineMenuIframeService["fadeInTimeout"]).toBeNull();
+    });
+
+    it("clears the delayed close timeout", () => {
+      jest.useFakeTimers();
+      jest.spyOn(globalThis, "clearTimeout");
+      autofillInlineMenuIframeService["delayedCloseTimeout"] = setTimeout(jest.fn(), 1000);
+
+      autofillInlineMenuIframeService.destroy();
+
+      expect(globalThis.clearTimeout).toHaveBeenCalled();
+      expect(autofillInlineMenuIframeService["delayedCloseTimeout"]).toBeNull();
+    });
+
+    it("clears the mutation observer iterations reset timeout", () => {
+      jest.useFakeTimers();
+      jest.spyOn(globalThis, "clearTimeout");
+      autofillInlineMenuIframeService["mutationObserverIterationsResetTimeout"] = setTimeout(
+        jest.fn(),
+        1000,
+      );
+
+      autofillInlineMenuIframeService.destroy();
+
+      expect(globalThis.clearTimeout).toHaveBeenCalled();
+      expect(autofillInlineMenuIframeService["mutationObserverIterationsResetTimeout"]).toBeNull();
+    });
+
+    it("unobserves the iframe mutation observer", () => {
+      const disconnectSpy = jest.spyOn(
+        autofillInlineMenuIframeService["iframeMutationObserver"],
+        "disconnect",
+      );
+
+      autofillInlineMenuIframeService.destroy();
+
+      expect(disconnectSpy).toHaveBeenCalled();
+    });
+
+    it("removes the port message listeners and disconnects the port", () => {
+      autofillInlineMenuIframeService.destroy();
+
+      expect(portSpy.onMessage.removeListener).toHaveBeenCalledWith(handlePortMessageSpy);
+      expect(portSpy.onDisconnect.removeListener).toHaveBeenCalledWith(handlePortDisconnectSpy);
+      expect(portSpy.disconnect).toHaveBeenCalled();
+      expect(autofillInlineMenuIframeService["port"]).toBeNull();
+    });
+
+    it("handles the case when the port is null", () => {
+      autofillInlineMenuIframeService["port"] = null;
+
+      expect(() => autofillInlineMenuIframeService.destroy()).not.toThrow();
+    });
+
+    it("handles the case when the iframe is undefined", () => {
+      autofillInlineMenuIframeService["iframe"] = undefined as any;
+
+      expect(() => autofillInlineMenuIframeService.destroy()).not.toThrow();
+    });
+  });
+
+  describe("clearAriaAlert", () => {
+    it("clears the aria alert timeout when it exists", () => {
+      jest.useFakeTimers();
+      jest.spyOn(globalThis, "clearTimeout");
+      autofillInlineMenuIframeService["ariaAlertTimeout"] = setTimeout(jest.fn(), 1000);
+
+      autofillInlineMenuIframeService.clearAriaAlert();
+
+      expect(globalThis.clearTimeout).toHaveBeenCalled();
+      expect(autofillInlineMenuIframeService["ariaAlertTimeout"]).toBeNull();
+    });
+
+    it("does nothing when the aria alert timeout is null", () => {
+      jest.spyOn(globalThis, "clearTimeout");
+      autofillInlineMenuIframeService["ariaAlertTimeout"] = null;
+
+      autofillInlineMenuIframeService.clearAriaAlert();
+
+      expect(globalThis.clearTimeout).not.toHaveBeenCalled();
+    });
+  });
+
+  describe("unobserveIframe", () => {
+    it("disconnects the iframe mutation observer", () => {
+      autofillInlineMenuIframeService.initMenuIframe();
+      const disconnectSpy = jest.spyOn(
+        autofillInlineMenuIframeService["iframeMutationObserver"],
+        "disconnect",
+      );
+
+      autofillInlineMenuIframeService["unobserveIframe"]();
+
+      expect(disconnectSpy).toHaveBeenCalled();
+    });
+
+    it("handles the case when the mutation observer is undefined", () => {
+      autofillInlineMenuIframeService["iframeMutationObserver"] = undefined as any;
+
+      expect(() => autofillInlineMenuIframeService["unobserveIframe"]()).not.toThrow();
+    });
+  });
+
+  describe("observeIframe", () => {
+    beforeEach(() => {
+      autofillInlineMenuIframeService.initMenuIframe();
+    });
+
+    it("observes the iframe for attribute mutations", () => {
+      const observeSpy = jest.spyOn(
+        autofillInlineMenuIframeService["iframeMutationObserver"],
+        "observe",
+      );
+
+      autofillInlineMenuIframeService["observeIframe"]();
+
+      expect(observeSpy).toHaveBeenCalledWith(autofillInlineMenuIframeService["iframe"], {
+        attributes: true,
+      });
+    });
+  });
 });