diff --git a/packages/browser/src/browser/__tests__/integration.test.ts b/packages/browser/src/browser/__tests__/integration.test.ts
index 5ff09ce05..5017c8b20 100644
--- a/packages/browser/src/browser/__tests__/integration.test.ts
+++ b/packages/browser/src/browser/__tests__/integration.test.ts
@@ -213,6 +213,57 @@ describe('Initialization', () => {
     })
   })
 
+  describe('bufferKey', () => {
+    const overrideKey = 'myKey'
+    const buffer = {
+      foo: 'bar',
+    }
+
+    beforeEach(() => {
+      ;(window as any)[overrideKey] = buffer
+    })
+    afterEach(() => {
+      delete (window as any)[overrideKey]
+    })
+    it('should default to window.analytics', async () => {
+      const defaultObj = { original: 'default' }
+      ;(window as any)['analytics'] = defaultObj
+
+      await AnalyticsBrowser.load({
+        writeKey,
+        plugins: [
+          {
+            ...xt,
+            load: async () => {
+              expect(getGlobalAnalytics()).toBe(defaultObj)
+            },
+          },
+        ],
+      })
+      expect.assertions(1)
+    })
+
+    it('should set the global window key for the analytics buffer with the setting option', async () => {
+      await AnalyticsBrowser.load(
+        {
+          writeKey,
+          plugins: [
+            {
+              ...xt,
+              load: async () => {
+                expect(getGlobalAnalytics()).toBe(buffer)
+              },
+            },
+          ],
+        },
+        {
+          bufferKey: overrideKey,
+        }
+      )
+      expect.assertions(1)
+    })
+  })
+
   describe('Load options', () => {
     it('gets high entropy client hints if set', async () => {
       ;(window.navigator as any).userAgentData = {
diff --git a/packages/browser/src/browser/index.ts b/packages/browser/src/browser/index.ts
index c4fcd939c..e859e8866 100644
--- a/packages/browser/src/browser/index.ts
+++ b/packages/browser/src/browser/index.ts
@@ -26,7 +26,7 @@ import { popSnippetWindowBuffer } from '../core/buffer/snippet'
 import { ClassicIntegrationSource } from '../plugins/ajs-destination/types'
 import { attachInspector } from '../core/inspector'
 import { Stats } from '../core/stats'
-import { getGlobalAnalytics } from './utils'
+import { getGlobalAnalytics, setGlobalAnalyticsKey } from './utils'
 
 export interface LegacyIntegrationConfiguration {
   /* @deprecated - This does not indicate browser types anymore */
@@ -149,10 +149,9 @@ function hasTsubMiddleware(settings: LegacySettings): boolean {
  */
 function flushPreBuffer(
   analytics: Analytics,
-  buffer: PreInitMethodCallBuffer,
-  bufferKey?: string
+  buffer: PreInitMethodCallBuffer
 ): void {
-  const calls = getGlobalAnalytics(bufferKey)
+  const calls = getGlobalAnalytics()
   buffer.push(...popSnippetWindowBuffer(calls))
   flushSetAnonymousID(analytics, buffer)
   flushOn(analytics, buffer)
@@ -163,10 +162,9 @@ function flushPreBuffer(
  */
 async function flushFinalBuffer(
   analytics: Analytics,
-  buffer: PreInitMethodCallBuffer,
-  bufferKey?: string
+  buffer: PreInitMethodCallBuffer
 ): Promise<void> {
-  const calls = getGlobalAnalytics(bufferKey)
+  const calls = getGlobalAnalytics()
   // Call popSnippetWindowBuffer before each flush task since there may be
   // analytics calls during async function calls.
   buffer.push(...popSnippetWindowBuffer(calls))
@@ -293,6 +291,7 @@ async function loadAnalytics(
   options: InitOptions = {},
   preInitBuffer: PreInitMethodCallBuffer
 ): Promise<[Analytics, Context]> {
+  if (options.bufferKey) setGlobalAnalyticsKey(options.bufferKey)
   // this is an ugly side-effect, but it's for the benefits of the plugins that get their cdn via getCDN()
   if (settings.cdnURL) setGlobalCDNUrl(settings.cdnURL)
 
@@ -317,7 +316,7 @@ async function loadAnalytics(
   Stats.initRemoteMetrics(legacySettings.metrics)
 
   // needs to be flushed before plugins are registered
-  flushPreBuffer(analytics, preInitBuffer, options.bufferKey)
+  flushPreBuffer(analytics, preInitBuffer)
 
   const ctx = await registerPlugins(
     settings.writeKey,
@@ -345,7 +344,7 @@ async function loadAnalytics(
     analytics.page().catch(console.error)
   }
 
-  await flushFinalBuffer(analytics, preInitBuffer, options.bufferKey)
+  await flushFinalBuffer(analytics, preInitBuffer)
 
   return [analytics, ctx]
 }
diff --git a/packages/browser/src/browser/utils.ts b/packages/browser/src/browser/utils.ts
index 2051aed38..6bd1dae1b 100644
--- a/packages/browser/src/browser/utils.ts
+++ b/packages/browser/src/browser/utils.ts
@@ -1,12 +1,23 @@
 import { AnalyticsSnippet } from './standalone-interface'
 
+/**
+ * Stores the global window analytics key
+ */
+let _globalAnalyticsKey = 'analytics'
+
 /**
  * Gets the global analytics instance/buffer
  * @param key name of the window property where the buffer is stored (default: analytics)
  * @returns AnalyticsSnippet
  */
-export function getGlobalAnalytics(
-  key = 'analytics'
-): AnalyticsSnippet | undefined {
-  return (window as any)[key]
+export function getGlobalAnalytics(): AnalyticsSnippet | undefined {
+  return (window as any)[_globalAnalyticsKey]
+}
+
+/**
+ * Replaces the global window key for the analytics/buffer object
+ * @param key key name
+ */
+export function setGlobalAnalyticsKey(key: string) {
+  _globalAnalyticsKey = key
 }
diff --git a/packages/consent/consent-tools-integration-tests/src/page-bundles/onetrust/index.ts b/packages/consent/consent-tools-integration-tests/src/page-bundles/onetrust/index.ts
index 4da0704ff..91a851283 100644
--- a/packages/consent/consent-tools-integration-tests/src/page-bundles/onetrust/index.ts
+++ b/packages/consent/consent-tools-integration-tests/src/page-bundles/onetrust/index.ts
@@ -12,4 +12,4 @@ oneTrust(analytics, {
 ;(window as any).analytics = analytics
 
 analytics.load({ writeKey: '9lSrez3BlfLAJ7NOChrqWtILiATiycoc' })
-void getGlobalAnalytics().page().then(console.log)
+void getGlobalAnalytics()?.page().then(console.log)
diff --git a/packages/core/src/task/__tests__/task-group.test.ts b/packages/core/src/task/__tests__/task-group.test.ts
new file mode 100644
index 000000000..e484b95ef
--- /dev/null
+++ b/packages/core/src/task/__tests__/task-group.test.ts
@@ -0,0 +1,26 @@
+import { createTaskGroup } from '../task-group'
+
+function sleep(ms: number) {
+  return new Promise((resolve) => setTimeout(resolve, ms))
+}
+
+describe('TaskGroup', () => {
+  it('works with concurrent operations', async () => {
+    const group = createTaskGroup()
+    const a = jest.fn()
+    const b = jest.fn()
+
+    void group.run(async () => {
+      await sleep(100)
+      a()
+    })
+    void group.run(async () => {
+      await sleep(1000)
+      b()
+    })
+
+    await group.done()
+    expect(a).toBeCalled()
+    expect(b).toBeCalled()
+  })
+})