Handling old browser versions after deployment
Hey *,
we are facing issues due to browsers out in the wild running on older versions of our frontend. We encountered 2 scenarios each having bugs, which get fixed after hard reloading the browser.
1. old version of the code -> hard relaod need to get the bug fix after deployment
2. wrong env config value -> hard reload needed to get the updated env config
Now we are looking for a solution to have nuxt handle it, since we can not rely on our user base performing hard reloads in the browser.
To me it feels this must be a common issue in any real world nuxt app. What mechanism does come nuxt with to solve this?
Cheers
3 Replies
Hi @martn.st. I'm kapa.ai, your friendly support bot. I will try to answer your question by searching through the knowledge base. :wave:
----------------------
Nuxt provides built-in mechanisms to help address the issue of users running outdated frontend code or stale environment config after a deployment—both of which typically require a "hard reload" to resolve.
1. Outdated JS Chunks (Old Code)
When a new deployment happens, users with open sessions may still have the old JS chunks cached. If they navigate to a route that requires a new chunk (e.g., a lazily loaded component), the browser may fail to load it, resulting in errors or a broken app. Nuxt detects these "chunk loading errors" and, by default, will perform a reload of the application when such an error occurs during route navigation. This helps users automatically recover from these issues without manual intervention.
You can further control this behavior with the
experimental.emitRouteChunkError option:
- Default: Nuxt reloads the app on navigation if a chunk fails to load.
- 'automatic-immediate': With this setting, Nuxt will immediately reload the app as soon as a chunk error is detected, not waiting for navigation. This is especially useful for live apps where lazy-loaded components are replaced after deployment. To enable this, set emitRouteChunkError: 'automatic-immediate' in your config. This triggers a reloadNuxtApp call right when the error is detected, helping users get the latest code automatically feat(nuxt): add a plugin that triggers an immediate reload on chunkError & manifest update Docs > 4.x > Getting-started > Error Handling.
2. Stale Environment Config
If your environment config changes (e.g., .env variables), Nuxt can also trigger a hard reload to ensure the latest config is loaded. There is a fix in place that forces a fresh cache and reloads Nuxt when .env changes are detected fix(nuxi): hard-reload nuxt when .env changes.
3. Additional Considerations
- Browser Cache for Payloads: Recent improvements in Nuxt (see perf(nuxt): use browser cache for payloads) help manage memory and cache for payloads, but the main mechanism for ensuring users get the latest code/config is the chunk error reload.
- Manual Cache Purge: If you use a CDN (like Cloudflare), you may also need to purge the CDN cache after each deployment to avoid serving stale assets Github Issue: Failed to fetch dynamically imported module.
Summary
Nuxt's chunk error handling and environment reload features are designed to address exactly the scenarios you described, ensuring users are automatically updated to the latest frontend code and config after deployment, without requiring them to manually perform a hard reload.
To enable immediate reloads on chunk errors, set:
This will help keep your users on the latest version of your app automatically.
----------------------
Note: you can ask me a follow up question by @ mentioning me again :speech_balloon:
----------------------<@825874012462645258> Kapa.ai is still learning and improving, please let me know how I did by reacting below.
okay. we have are using keep alive to cache pages.
I guess with this changes of "chunk loading errors" are rather low? Meaning this strategy might not be succicient for us.