Fwiw, in Bash, alt-shift-3 will prepend the current command with # and start a new command.
More generally, it's alt-#. On an ISO (e.g. UK) keyboard layout, shift-3 isn't a hash.
Thank you so much! I do this constantly. For me it was Ctrl-A Shift-3 Enter - two keystrokes too many.
More generally, it's alt-#. On an ISO (e.g. UK) keyboard layout, shift-3 isn't a hash.