'The ReadableStream reader was released' error since 8.33.1

[artaommahe]

Is there an existing issue for this?

• I have checked for existing issues https://github.com/getsentry/sentry-javascript/issues
• I have reviewed the documentation https://docs.sentry.io/
• I am using the latest SDK release https://github.com/getsentry/sentry-javascript/releases

How do you use Sentry?

Sentry Saas (sentry.io)

Which SDK are you using?

@sentry/browser

SDK Version

8.33.1

Framework Version

React 18.3.1

Link to Sentry event

https://instruqt.sentry.io/issues/5974845065/?alert_rule_id=4248301&alert_type=issue&environment=production&notification_uuid=2239a562-e5ee-4f80-8733-5f2b64db27a2&project=1218778&referrer=slack

Reproduction Example/SDK Setup

Sentry.init({
  dsn: '...',
  release: import.meta.env.VITE_REACT_APP_VERSION,
  environment: isDev ? 'development' : 'production',
  allowUrls: ['...'],
  normalizeDepth: 5,
  integrations: [
    Sentry.reactRouterV6BrowserTracingIntegration({
      useEffect,
      useLocation,
      useNavigationType,
      createRoutesFromChildren,
      matchRoutes,
    }),
    Sentry.replayIntegration(),
  ],
  tracesSampleRate: isDev ? 1 : 0.1,
  replaysSessionSampleRate: isDev ? 1 : 0.1,
  replaysOnErrorSampleRate: 1.0,
  beforeBreadcrumb: excludeGraphQLFetch,
  ignoreErrors: [/^ResizeObserver.*/, /^AbortError.*/, 'Object Not Found Matching Id'],
  beforeSend(event) {
    if (event.exception?.values?.some(checkCancellationException)) {
      return null;
    }

    return event;
  },
});

Steps to Reproduce

Since 8.33.1 update we got new errors in the sentry 'The ReadableStream reader was released' with pointing to the sentry's code

# ../../node_modules/@sentry/utils/build/esm/instrument/fetch.js in resolveResponse at line 157:20

    responseReader.releaseLock();

Looks like the only browser that produces this error for us is Pale Moon 33.4.0

Expected Result

no error from the sentry library

Actual Result

(provided above)

[lforst]

Thanks for reporting this! Super interesting bug. In theory, there is no possible way this could reject since the return values of ReadableStreamDefaultReader.releaseLock() and ReadableStreamBYOBReader.releaseLock() should not return promises. I assume this is specific to the Pale Moon browser.

Since I assume the usage of Pale Moon is rather low, I am a bit hesitant to add edge case handling to the SDK at the cost of bundle size for basically everybody else.

For now, I recommend you add ignoreErrors: ["The ReadableStream reader was released."] to your Sentry.init() which will ignore this error. It should not have any effect on the functionality of your page.

I found that pale moon only recently added support for the ReadableStreams API so maybe they still have to figure some stuff out: https://www.palemoon.org/releasenotes.shtml#:~:text=Added%20an%20initial%20implementation%20of%20the%20ReadableStreams%20API

If more people run into this problem we'll think about adding special casing or a default ignore rule to the SDK.

[getsantry]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you remove the label Waiting for: Community, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀