cannot create R notebooks in v7

[janxkoci]

Description

In the new Notebook 7 interface, I see no direct way to create notebooks with alternative kernels, such as irkernel for R. Creating new notebook from menu or the "new" dropdown always creates a Python notebook.

Reproduce

1. Go to File > New > Notebook
2. After new notebook opens in new tab, see the kernel in top right corner - it's Python.
3. Click the kernel name.
4. Here I get to select the R kernel and switch to it.

Expected behavior

I should be able to directly create R notebooks, just like I can in Notebook Classic or Jupyterlab, without going through the Python kernel first.

Context

• Operating System and version: Linux Ubuntu 22.04
• Browser and version: Firefox 119.0.1
• Jupyter Notebook version: 7.0.6
• notebook installed with mamba 1.4.2

[jtpio]

This should be fixed by #7255 (to be released soon), with the "New" dropdown mimicking allowing to select a kernel, similar to the behavior of the classic notebook:

create-new-r-notebook.webm