Safari service worker issue

[rebelchris]

Changes

Describe what this PR does

• The service worker (sw.ts) now detects Safari (excluding other browsers that spoof the UA) and immediately unregisters itself to prevent the WebKitInternal:0 crash.
• _app.tsx has been updated to proactively detect Safari, unregister any existing /sw.js service workers, and prevent Serwist from being registered for Safari users.
• Trade-off: Safari users will temporarily lose service worker caching and offline capabilities, but the site will load reliably without crashing.

Events

No new tracking events.

Experiment

No new experiments.

Manual Testing

Caution

Please make sure existing components are not breaking/affected by this PR

On those affected packages:

• Have you done sanity checks in the webapp?

Did you test on actual mobile devices?

• iOS (Chrome and Safari) - Crucial to validate the fix on physical Safari devices, especially with existing service worker caches.

ENG-210

---

Linear Issue: ENG-210

 

Preview domain

https://cursor-eng-210-safari-service-wo.preview.app.daily.dev

[cursor]

Cursor Agent can help with this pull request. Just @cursor in comments and I'll start working on changes in this branch.
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Project	Deployment	Review	Updated (UTC)
daily-webapp	Ready	Preview	Dec 23, 2025 2:04pm

1 Skipped Deployment

Project	Deployment	Review	Updated (UTC)
storybook	Ignored		Dec 23, 2025 2:04pm

[idoshamun]

Have you managed to reproduce and validate the fix?

[rebelchris]

@idoshamun I tested it before it was indeed the safari crash loop on outdated sw, haven't validated though. it's just vibes that disable it all together for safari for now.