Browser freeze caused by React traces

[etienne-scaleway]

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?

Self-hosted/on-premise

Which SDK are you using?

@sentry/react

SDK Version

10.10.0

Framework Version

React 19.2.0

Link to Sentry event

No response

Reproduction Example/SDK Setup

init({
  // ...
  integrations: [
      browserTracingIntegration(),
  ]
})

Steps to Reproduce

My app started to randomly freeze for a few second every now a then, I figured out that the freezing was happening when certain errors were send by sentry, those errors have a huge payload (~1MB for the one I looked at). This payload appear to be caused by a lot or spans generated by React

        {
            "data": {
                "sentry.origin": "auto.resource.browser.metrics",
                "sentry.op": "measure",
                "sentry.browser.measure.detail.devtools": "{\"properties\":[[\"Component name\",\"Router2\"],[\"Method name\",\"this.setState()\"]],\"track\":\"Blocking\",\"trackGroup\":\"Scheduler ⚛\",\"color\":\"primary-light\"}"
            },
            "description": "Update",
            "op": "measure",
            "parent_span_id": "bbc16784926ef270",
            "span_id": "b6eef92fdcbc9e04",
            "start_timestamp": 1761213364.9232,
            "timestamp": 1761213364.9232998,
            "trace_id": "56586792ec074c77b6bc8ae28f0f2daa",
            "origin": "auto.resource.browser.metrics"
        },

My understanding is that this is caused by the new Performance tracks introduced by React.

The issue is not present in production (only in dev) which make sense as React does not generate traces in productions build.

Note

We are not using the latest SDK, I'll try to update later didn't had time yet and I didn't see any mention of this issues in the latest release notes.

Additional Context

_{Tip: React with 👍 to help prioritize this issue. Please use comments to provide useful context, avoiding +1 or me too, to help us triage it.}

[linear]

JS-1088

[AbhiPrasad]

This was fixed in https://github.com/getsentry/sentry-javascript/releases/tag/10.20.0! Please upgrade and give it a try.