InvalidStateError: Failed to execute 'send' on 'WebSocket': Still in CONNECTING state.

## Error

```
Failed to execute 'send' on 'WebSocket': Still in CONNECTING state.
```

## Stack trace

```
/asset/asset.js:2 in e.WebsocketManager.send
/asset/asset.js:2 in e.EntityManager.flush
/asset/asset.js:2 in e.EntityManager.deactivateEntityAtKey
/asset/asset.js:2 in e.EntityManager.onLocationChange
../node_modules/@sentry/browser/src/helpers.ts:117 in sentryWrapped
/asset/asset.js:2 in History.pushState
../node_modules/@hotwired/turbo/dist/turbo.es2017-esm.js:2291 in History.update
../node_modules/@hotwired/turbo/dist/turbo.es2017-esm.js:3619 in FrameController.changeHistory
../node_modules/@hotwired/turbo/dist/turbo.es2017-esm.js:3559 in FrameController.loadFrameResponse
../node_modules/@hotwired/turbo/dist/turbo.es2017-esm.js:3442 in FrameController.loadResponse
```

## Tracking Details
- **Project**: exercism-js
- **Sentry**: [InvalidStateError: Failed to execute 'send' on 'WebSocket': Still in CONNECTING state.](https://thalamus-ai.sentry.io/issues/144962850/)
- **Culprit**: e.WebsocketManager.send(asset/asset)
- **First seen:** Sep 4, 2026

Start with the Sentry report and the minified asset/asset.js stack trace, especially WebsocketManager.send and EntityManager.flush during Turbo navigation. Trace how the WebSocket reaches send while still connecting and identify the relevant source and reproduction path. Done means the reported error no longer occurs during the affected history or frame navigation.

Written by the indexing model from the issue text.