@sentry/nextjs `autoInstrumentServerFunctions` breaks next.js' font optimization

[klaasman]

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/nextjs

SDK Version

7.54.0

Framework Version

7.54.0

Link to Sentry event

No response

SDK Setup

Sentry.init({
dsn: SENTRY_DSN,
tracesSampleRate: 1.0,
});

Steps to Reproduce

Clone the following repository: https://github.com/klaasman/sentry-nextjs-font-inlining-bug

1. npm install
2. npm run build
3. open ./.next/server/pages/index.html, you will see that the font-loading is inlined (search for @font-face)
4. now open next.config.js and comment out the autoInstrumentServerFunctions line
5. npm run build
6. open ./.next/server/pages/index.html, you will see that the font-loading is not inlined anymore (search for @font-face)

Expected Result

I expected next.js font optimization feature to work.

Actual Result

The autoInstrumentServerFunctions somehow disables next.js' font inlining feature. This setting is turned on by default, in this repository it is turned off in the next.config.js file.

[lforst]

Thanks for writing in! We'll take a look at this!

[klaasman]

Thanks - you can find more info in the README of the reproduction github repository.

[github-actions]

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 label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

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