NotFoundError: Failed to execute 'insertBefore' on 'Node': The node before which the new node is to be inserted is not a child of this node.

## Error

```
Failed to execute 'insertBefore' on 'Node': The node before which the new node is to be inserted is not a child of this node.
```

## Stack trace

```
s
div
../node_modules/react-i18next/dist/es/Trans.js:6 in Trans
div
../app/javascript/components/student/mentoring-session/SessionInfo.tsx:12 in SessionInfo
header
div
div
../app/javascript/components/common/SplitPane.tsx:12 in SplitPane
div
```

## Tracking Details
- **Project**: exercism-js
- **Sentry**: [NotFoundError: Failed to execute 'insertBefore' on 'Node': The node before which the new node is to be inserted is not a child of this node.](https://thalamus-ai.sentry.io/issues/100211862/)
- **Culprit**: Wj(react-dom/cjs/react-dom.production)
- **First seen:** Mar 2, 2026