fix(sentry-config): Ignore browser-injected __firefox__ and DarkReader errors

[sentry]

DESCRIBE YOUR PR

This PR addresses issue CHANGELOG-81, where ReferenceError: Can't find variable: __firefox__ and ReferenceError: Can't find variable: DarkReader were reported on the /changelog/:slug pages.

The root cause was identified as third-party scripts injected by the Brave browser on iOS (which is based on Firefox iOS). These scripts attempt to access window.__firefox__ and DarkReader, which are not always defined in the page's execution context, leading to ReferenceError.

To resolve this, ignoreErrors patterns have been added to the Sentry.init configuration in src/instrumentation-client.ts. This prevents these specific, non-application-related errors from being reported to Sentry, reducing noise and focusing on actual application issues.

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PRE-MERGE CHECKLIST

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• Checked Vercel preview for correctness, including links
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LEGAL BOILERPLATE

Look, I get it. The entity doing business as "Sentry" was incorporated in the State of Delaware in 2015 as Functional Software, Inc. and is gonna need some rights from me in order to utilize my contributions in this here PR. So here's the deal: I retain all rights, title and interest in and to my contributions, and by keeping this boilerplate intact I confirm that Sentry can use, modify, copy, and redistribute my contributions, under Sentry's choice of terms.

EXTRA RESOURCES

• Sentry Docs contributor guide

Fixes CHANGELOG-81

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Project	Deployment	Actions	Updated (UTC)
develop-docs	Ready	Preview, Comment	May 8, 2026 3:26am
sentry-docs	Ready	Preview, Comment	May 8, 2026 3:26am