Unable to open a file with a custom scheme using the NotebookEditor

[DonJayamanne]

• VSCode Version:
• OS Version:

Steps to Reproduce:

1. Register *.ipnb files to be opened with Notebook Editor
2. Open NB as follows:

const fileName = 'untitled.ipynb';
const fileUri = Uri.file(fileName);
const uri = fileUri.with({ scheme: 'untitled', path: fileName });
commands.executeCommand('vscode.open', uri);

Note:

• Changing scheme to something else fixes this issue.

Error displayed

@rebornix /cc