From f137ca92414c4bfe332b28b2ce6827c351758b24 Mon Sep 17 00:00:00 2001
From: Lukas Stracke <lukas.stracke@sentry.io>
Date: Wed, 29 Jul 2026 14:34:47 +0200
Subject: [PATCH 1/3] ref(core): Tree-shake `spanStreamingIntegration` when
 tracing is disabled

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
---
 packages/browser/src/sdk.ts                | 3 +++
 packages/core/src/server-runtime-client.ts | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/packages/browser/src/sdk.ts b/packages/browser/src/sdk.ts
index 84f4940c8b41..4419b800591f 100644
--- a/packages/browser/src/sdk.ts
+++ b/packages/browser/src/sdk.ts
@@ -28,6 +28,8 @@ import { makeFetchTransport } from './transports/fetch';
 import { normalizeStringifyValue } from './normalizeStringifyValue';
 import { checkAndWarnIfIsEmbeddedBrowserExtension } from './utils/detectBrowserExtension';
 
+declare const __SENTRY_TRACING__: boolean;
+
 /** Get the default integrations for the browser SDK. */
 export function getDefaultIntegrations(_options: Options): Integration[] {
   /**
@@ -120,6 +122,7 @@ export function init(options: BrowserOptions = {}): Client | undefined {
   });
 
   if (
+    (typeof __SENTRY_TRACING__ === 'undefined' || __SENTRY_TRACING__) &&
     options.traceLifecycle !== 'static' &&
     !integrations.some(integration => integration.name === SPAN_STREAMING_INTEGRATION_NAME)
   ) {
diff --git a/packages/core/src/server-runtime-client.ts b/packages/core/src/server-runtime-client.ts
index e0426e558ed3..159c4aeb3b93 100644
--- a/packages/core/src/server-runtime-client.ts
+++ b/packages/core/src/server-runtime-client.ts
@@ -28,6 +28,8 @@ export interface ServerRuntimeClientOptions extends ClientOptions<BaseTransportO
   serverName?: string;
 }
 
+declare const __SENTRY_TRACING__: boolean;
+
 /**
  * The Sentry Server Runtime Client SDK.
  */
@@ -47,6 +49,7 @@ export class ServerRuntimeClient<
     // is required to flush spans. We add it here so the individual server SDKs don't have to.
     // A user-provided `spanStreamingIntegration` always takes precedence over the one we add.
     if (
+      (typeof __SENTRY_TRACING__ === 'undefined' || __SENTRY_TRACING__) &&
       options.traceLifecycle !== 'static' &&
       !options.integrations.some(i => i.name === SPAN_STREAMING_INTEGRATION_NAME)
     ) {

From 5f02cef7765cc95d9cfa19787c8263a6253ebe9e Mon Sep 17 00:00:00 2001
From: Lukas Stracke <lukas.stracke@sentry.io>
Date: Tue, 4 Aug 2026 18:49:29 +0200
Subject: [PATCH 2/3] add size-limit entry for tracing disabled flag

---
 .size-limit.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/.size-limit.js b/.size-limit.js
index b775eaadb04f..971b6b575449 100644
--- a/.size-limit.js
+++ b/.size-limit.js
@@ -35,6 +35,31 @@ module.exports = [
       return config;
     },
   },
+  {
+    name: '@sentry/browser - with treeshaking flags incl. tracing',
+    path: 'packages/browser/build/npm/esm/prod/index.js',
+    import: createImport('init'),
+    gzip: true,
+    limit: '34 KB',
+    disablePlugins: ['@size-limit/esbuild'],
+    modifyWebpackConfig: function (config) {
+      const webpack = require('webpack');
+
+      config.plugins.push(
+        new webpack.DefinePlugin({
+          __SENTRY_DEBUG__: false,
+          __RRWEB_EXCLUDE_SHADOW_DOM__: true,
+          __RRWEB_EXCLUDE_IFRAME__: true,
+          __SENTRY_EXCLUDE_REPLAY_WORKER__: true,
+          __SENTRY_TRACING__: false,
+        }),
+      );
+
+      config.optimization.minimize = true;
+
+      return config;
+    },
+  },
   {
     name: '@sentry/browser (incl. Tracing)',
     path: 'packages/browser/build/npm/esm/prod/index.js',

From 0fe627d7ba8f835e65484fae64968cca83b58d65 Mon Sep 17 00:00:00 2001
From: Lukas Stracke <lukas.stracke@sentry.io>
Date: Tue, 4 Aug 2026 19:03:21 +0200
Subject: [PATCH 3/3] fix misleading size check name and adjust limit

---
 .size-limit.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.size-limit.js b/.size-limit.js
index 971b6b575449..9dafaed4545e 100644
--- a/.size-limit.js
+++ b/.size-limit.js
@@ -36,11 +36,11 @@ module.exports = [
     },
   },
   {
-    name: '@sentry/browser - with treeshaking flags incl. tracing',
+    name: '@sentry/browser - with treeshaking flags tracing without tracing',
     path: 'packages/browser/build/npm/esm/prod/index.js',
     import: createImport('init'),
     gzip: true,
-    limit: '34 KB',
+    limit: '32 KB',
     disablePlugins: ['@size-limit/esbuild'],
     modifyWebpackConfig: function (config) {
       const webpack = require('webpack');