Error reports from most language kernels running in IPython/Jupyter Notebooks indicate the line on which the error occurred; but (at least by default) no line numbers are in
For me, ctrl + m is used to save the webpage as png, so it does not work properly. But I find another way.
On the toolbar, there is a bottom named open the command paletee, you can click it and type in the line, and you can see the toggle cell line number here.