VSCode arrow select mode how to get out?

Question

I don't know how did I get into this mode, but whenever I press the arrow buttons, the cursor moved and selected the text it passed. As if the Shift key is pressed.

What is it and how to get out?

I have to close and reopen vscode to clear it.

Edit: The mode is entered by pressing Ctrl-Space. Seems an Emacs mark set mode.

Answer 1

OK, figured it out. It is Emacs mark set mode. Entered by pressing Ctrl-Space.

To exit, select something first then press Ctrl-g