Why did the tree view on the left disappear, leaving only a flat list?

BabelEdit displays translation IDs in a tree view only when it can clearly detect a hierarchical structure - either through nested JSON objects or keys that use dots (.) as namespace separators.

{
    "demo": {
        "greeting": "Hello",
        "title": "..."
    }
}

{
    "demo.greeting": "Hello",
    "demo.title": "..."
}

However, if you add a key like "demo": "a demo app", BabelEdit can no longer determine whether "demo" should be a namespace or a translation ID. As a result, the tree view is deactivated because BabelEdit doesn't support this mixed structure.

To restore the tree view:

• Remove the conflicting keys (e.g., "demo": "a demo app").
• Then, go to Configuration → Format: to switch back to the tree view format.