jupyter: visual debugger exists now #265

I didn't know about this, so maybe good to say?: https://blog.jupyter.org/a-visual-debugger-for-jupyter-914e61716559

How to use: click the "bug" symbol in the notebook view. It opens in the right sidebar.
Requires ipykernel>=6 (which is included in default anaconda), or a kernel for another language which supports the debug protocol.