Multicursor selection in Jupyter without mouse

On GitHub, I found this. It is not precisely what you asked for, but speeds up my use of Jupyter considerably.

• Place cursor in the desired spot
• Hold Ctrl + Alt
• Hold your left mouse button and drag mouse over the lines where you want a cursor

This places the mouse cursor in the same column of each line. It works particularly well if you need a mouse cursor at the beginning of each line.

If you like vi/vim keybindings, take a look at the excellent jupyter-vim-binding, which adds additional keyboard editing modes to Jupyter notebook, similar to Vim.

After installing this extension, as in Vim, you can perform multicursor selection (block selection) with Ctrl+v.