diff --git a/packages/hub/src/hub.ts b/packages/hub/src/hub.ts
index e3c9bd96d436..2995b0edf98f 100644
--- a/packages/hub/src/hub.ts
+++ b/packages/hub/src/hub.ts
@@ -351,13 +351,6 @@ export class Hub implements HubInterface {
     return this._callExtensionMethod('startTransaction', context, customSamplingContext);
   }
 
-  /**
-   * @inheritDoc
-   */
-  public traceHeaders(): { [key: string]: string } {
-    return this._callExtensionMethod<{ [key: string]: string }>('traceHeaders');
-  }
-
   /**
    * @inheritDoc
    */
diff --git a/packages/node/test/integrations/http.test.ts b/packages/node/test/integrations/http.test.ts
index c13f3bb90a0a..705ff6f8ebdb 100644
--- a/packages/node/test/integrations/http.test.ts
+++ b/packages/node/test/integrations/http.test.ts
@@ -9,7 +9,7 @@ import { NodeClient } from '../../src/client';
 import { Http as HttpIntegration } from '../../src/integrations/http';
 
 describe('tracing', () => {
-  function createTransactionOnScope() {
+  function createTransactionOnScope(): Transaction {
     const hub = new Hub(
       new NodeClient({
         dsn: 'https://dogsarebadatkeepingsecrets@squirrelchasers.ingest.sentry.io/12312012',
@@ -24,7 +24,10 @@ describe('tracing', () => {
     jest.spyOn(sentryCore, 'getCurrentHub').mockReturnValue(hub);
     jest.spyOn(hubModule, 'getCurrentHub').mockReturnValue(hub);
 
-    const transaction = hub.startTransaction({ name: 'dogpark' });
+    // we have to cast this to a Transaction (the class) because hub.startTransaction only returns a Transaction (the
+    // interface, which doesn't have things like spanRecorder) (and because @sentry/hub can't depend on @sentry/tracing,
+    // we can't fix that)
+    const transaction = hub.startTransaction({ name: 'dogpark' }) as Transaction;
     hub.getScope()?.setSpan(transaction);
 
     return transaction;
@@ -36,7 +39,7 @@ describe('tracing', () => {
       .reply(200);
 
     const transaction = createTransactionOnScope();
-    const spans = (transaction as Span).spanRecorder?.spans as Span[];
+    const spans = transaction.spanRecorder?.spans as Span[];
 
     http.get('http://dogs.are.great/');
 
@@ -55,7 +58,7 @@ describe('tracing', () => {
       .reply(200);
 
     const transaction = createTransactionOnScope();
-    const spans = (transaction as Span).spanRecorder?.spans as Span[];
+    const spans = transaction.spanRecorder?.spans as Span[];
 
     http.get('http://squirrelchasers.ingest.sentry.io/api/12312012/store/');
 
diff --git a/packages/tracing/src/hubextensions.ts b/packages/tracing/src/hubextensions.ts
index e041a9e33b3b..888b5b74ce77 100644
--- a/packages/tracing/src/hubextensions.ts
+++ b/packages/tracing/src/hubextensions.ts
@@ -13,20 +13,6 @@ import { IdleTransaction } from './idletransaction';
 import { Transaction } from './transaction';
 import { hasTracingEnabled } from './utils';
 
-/** Returns all trace headers that are currently on the top scope. */
-function traceHeaders(this: Hub): { [key: string]: string } {
-  const scope = this.getScope();
-  if (scope) {
-    const span = scope.getSpan();
-    if (span) {
-      return {
-        'sentry-trace': span.toTraceparent(),
-      };
-    }
-  }
-  return {};
-}
-
 /**
  * Makes a sampling decision for the given transaction and stores it on the transaction.
  *
@@ -212,9 +198,6 @@ export function _addTracingExtensions(): void {
     if (!carrier.__SENTRY__.extensions.startTransaction) {
       carrier.__SENTRY__.extensions.startTransaction = _startTransaction;
     }
-    if (!carrier.__SENTRY__.extensions.traceHeaders) {
-      carrier.__SENTRY__.extensions.traceHeaders = traceHeaders;
-    }
   }
 }
 
diff --git a/packages/tracing/src/transaction.ts b/packages/tracing/src/transaction.ts
index 536b5fc663c3..5af70cc3e52f 100644
--- a/packages/tracing/src/transaction.ts
+++ b/packages/tracing/src/transaction.ts
@@ -6,7 +6,7 @@ import {
   TransactionContext,
   TransactionMetadata,
 } from '@sentry/types';
-import { dropUndefinedKeys, isInstanceOf, logger } from '@sentry/utils';
+import { dropUndefinedKeys, logger } from '@sentry/utils';
 
 import { Span as SpanClass, SpanRecorder } from './span';
 
@@ -21,7 +21,7 @@ export class Transaction extends SpanClass implements TransactionInterface {
   /**
    * The reference to the current hub.
    */
-  private readonly _hub: Hub = (getCurrentHub() as unknown) as Hub;
+  private readonly _hub: Hub;
 
   private _trimEnd?: boolean;
 
@@ -35,13 +35,10 @@ export class Transaction extends SpanClass implements TransactionInterface {
   public constructor(transactionContext: TransactionContext, hub?: Hub) {
     super(transactionContext);
 
-    if (isInstanceOf(hub, Hub)) {
-      this._hub = hub as Hub;
-    }
-
     this.name = transactionContext.name || '';
     this.metadata = transactionContext.metadata || {};
     this._trimEnd = transactionContext.trimEnd;
+    this._hub = hub || getCurrentHub();
 
     // create a new sentry tracestate value if we didn't inherit one
     if (!this.metadata.tracestate?.sentry) {
diff --git a/packages/tracing/src/utils.ts b/packages/tracing/src/utils.ts
index 3bf0a17a1415..2a6ca3bf4423 100644
--- a/packages/tracing/src/utils.ts
+++ b/packages/tracing/src/utils.ts
@@ -80,15 +80,13 @@ export function extractSentrytraceData(header: string): TraceparentData | undefi
   return undefined;
 }
 
-type TracestateHeaderData = { sentry?: string; thirdparty?: string };
-
 /**
  * Extract data from an incoming `tracestate` header
  *
  * @param header
  * @returns Object containing data from the header
  */
-export function extractTracestateData(header: string): TracestateHeaderData {
+export function extractTracestateData(header: string): { sentry?: string; thirdparty?: string } {
   let sentryEntry, thirdPartyEntry, before, after;
 
   // find sentry's entry, if any
@@ -160,7 +158,8 @@ type SentryTracestateData = {
  * @returns the base64-encoded header value
  */
 export function computeTracestateValue(data: SentryTracestateData): string {
-  // `JSON.stringify` will drop keys with undefined values, but not ones with null values
+  // `JSON.stringify` will drop keys with undefined values, but not ones with null values, so this prevents
+  // `environment` and `release` from being dropped if they haven't been set by `Sentry.init`
   data.environment = data.environment || null;
   data.release = data.release || null;
 
diff --git a/packages/types/src/hub.ts b/packages/types/src/hub.ts
index 22948f3f2024..ab1b187f32e2 100644
--- a/packages/types/src/hub.ts
+++ b/packages/types/src/hub.ts
@@ -177,9 +177,6 @@ export interface Hub {
   /** Returns the integration if installed on the current client. */
   getIntegration<T extends Integration>(integration: IntegrationClass<T>): T | null;
 
-  /** Returns all trace headers that are currently on the top scope. */
-  traceHeaders(): { [key: string]: string };
-
   /**
    * @deprecated No longer does anything. Use use {@link Transaction.startChild} instead.
    */