TextDocument.onDidChangePath() not firing

Not sure if it’s a bug or I’m doing it wrong.

I can’t get onDidChangePath to fire. But onDidChangeSyntax does fire on the same document object.

const document = editor.document;
document.onDidChangePath((changedDocument, path) => {
    console.log("editor.document.onDidChangePath", changedDocument.uri, path);
});

document.onDidChangeSyntax((changedDocument, newSyntax) => {
    console.log("editor.document.onDidChangeSyntax", changedDocument.uri, newSyntax);
});

Same document, the second function fires when I change syntax, the first one never fires.

I try renaming a document from the context menu or by clicking and typing in the sidebar.
I try moving a document from the context menu or by clicking and dragging in the sidebar.

What action will get onDidChangePath to fire? Is it broken?

Tested on my other Mac and not working there either.