publicStripeKey: "" crash in env.js for self-hosted instances.

# Self-hosted dashboard blank screen — Stripe.js crashes on empty `publicStripeKey` ## Description The Nango dashboard renders a completely blank/black screen on self-hosted instances. The root cause is `stripe.js` attempting to initialize with an empty string, which throws an unhandled error that kills the entire React app. ## Console Error ``` Uncaught (in promise) IntegrationError: Please call Stripe() with your publishable key. You used an empty string. at stripe.js:1 ``` Additionally: ``` The Content Security Policy directive 'upgrade-insecure-requests' is ignored when delivered in a report-only policy. at stripe.js:1 ``` ## Root Cause The `/env.js` endpoint returns `"publicStripeKey": ""` for self-hosted instances (expected, since self-hosted doesn't use Stripe billing). However, the dashboard frontend code calls `Stripe("")` unconditionally without checking whether the key is a non-empty string first. **`/env.js` output:** ```json window._env = { "apiUrl": "https://nango.example.com", "publicStripeKey": "", "isCloud": false, "isHosted": true, "isEnterprise": false, "features": { "plan": false } } ``` Despite `isCloud: false` and `features.plan: false`, the Stripe initialization still runs and crashes. ## Environment - **Image:** `nangohq/nango-server:hosted` (also reproduced on `hosted-0.69.30`) - **Version:** 0.69.40+ (git hash `5fc90c54d6b4efc23bddd6652fbbc087621ebd8d`) - **Deployment:** Docker Compose via Coolify on Ubuntu 24 - **Self-hosted:** Yes, free tier ## Steps to Reproduce 1. Deploy `nangohq/nango-server:hosted` with standard self-hosted configuration per [[docs](https://nango.dev/docs/guides/platform/free-self-hosting/configuration)](https://nango.dev/docs/guides/platform/free-self-hosting/configuration) 2. Navigate to the dashboard URL in a browser 3. Observe blank/black screen 4. Open browser DevTools → Console → see `IntegrationError` from `stripe.js` ## Expected Behavior The dashboard should load normally on self-hosted instances. Stripe initialization should be gated behind a check like: ```javascript if (window._env.publicStripeKey && window._env.isCloud) { loadStripe(window._env.publicStripeKey); } ``` ## Workaround The API itself is unaffected — `/health` returns `{"result":"ok"}` and all OAuth/proxy/connection endpoints work normally. The issue is isolated to the dashboard UI. Integrations can be managed via the API or `@nangohq/node` SDK as a workaround. ## Impact This completely blocks dashboard access for all self-hosted users on the current `:hosted` tag. No configuration changes or documented environment variables resolve the issue.