My app is stuck loading after I publish it

The preview works. But on the live site the page shows a spinner, or "Loading…", and it never stops. Visitors wait a few seconds and leave, and nobody tells you.

A spinner that never stops almost always means the page asked for something and never got an answer. Here's how to find what.

Find the cause in 2 minutes

1. Open your live site on a computer and press F12.
2. Open the Console tab and reload the page. Copy the first red error. That's usually the answer.
3. Open the Network tab and reload again. Look for a request that's red, that has a status like 401, 404 or 500, or that stays "pending".
4. Note which address it was calling. That tells you which of the causes below it is.

The usual causes

• A setting the live site doesn't have. The app calls its database or backend using an address or key that was set for the preview, but never added to the live environment. The request goes nowhere, so the page waits forever. The console often shows undefined in an address, or a failed request.
• Your database is paused. On Supabase's free plan, a project is paused when it's quiet. Supabase's docs: "A Free plan project is considered inactive if it does not receive sufficient user database activity over the past week." A new app with few visitors can hit this. The fix is in your Supabase dashboard: open the project and click Resume project. Supabase gives "a 1-year window to restore the project" after it's paused.
• A login check that never finishes. The page waits to learn whether the visitor is signed in, and the answer never comes. This happens when the live address isn't in the sign-in settings, or when a signed-out visitor isn't handled at all. Try it in a private window: if the spinner shows only when you're signed out, this is it.
• A backend function that crashes. The page waits for a function that fails on the live site. Your builder's or host's function logs show the error.
• An error after the first screen. A script error stops the page before it replaces the spinner. That's the red console error from step 2.

Fix it in your builder

Paste this, with the error you copied:

My LIVE site (not the preview) is stuck on a loading spinner forever. The first console error is: [paste]. The request that fails or stays pending is: [paste the address]. Find why that request never answers on the live site, fix only that, and make the page show a clear message instead of an endless spinner if a request fails. Tell me how to check it in a private window.

Then publish and reload the live site in a private window, signed out and signed in.

Check what visitors actually get

Paste your app's link at vibe-fixer.com. An AI agent opens your live app on a phone and a computer like a new visitor, tells you where it gets stuck, and gives you the exact fix for one problem to paste into your builder, free. Then it re-tests the live app to prove it worked. No account needed.

Related: App shows a blank page after publishing · Works in the preview, breaks after deploy · Test your live app like a real customer