Stuck in command mode for newbie

[fomightez]

You are likely not stuck in the mode; it’s just that the border colors don’t change in that manner now in modern JupyterLab and Jupyter Notebook 7+.

See here for basically the same question from almost exactly a year ago.
This part here probably summarizes it most succinctly:

@fomightez

The specific color indicators don’t work that way anymore.
The ways to change mode work much the same way as noted.

Click inside a cell to enter the editing mode. The active cell box will acquire a blue highlight around it.

Enter command mode by pressing Esc or using the mouse to click outside a cell’s editor area. The code cells will not have any blue lines around them and instead will all appear gray.

If ever in doubt about your experience, go here and click the ‘launch binder’ badge. You’ll get a fresh temporary session on a remote machine with one of the latest versions of JupyterLab. You can use that and eliminate browser extensions as a variable by trying different browsers where you maybe didn’t install any extensions yet.