Beginner Tutorial 3. Your First Flowgraph

I got the flowgraph set up exactly as in the tutorial. Hit play and get this popup message:

The xterm executable " is missing.

You can change this setting in your gnurado.cnf, in section
[grc], 'xterm executable'.

This is the contents of gnuradio.cnf grc.conf

***************************************
# This file contains system wide configuration data for GNU Radio.
# You may override any setting on a per-user basis by editing
# ~/.gnuradio/config.conf

[grc]
global_blocks_path = /usr/share/gnuradio/grc/blocks:/usr/local/share/gnuradio/grc/blocks
local_blocks_path =
default_flow_graph =
xterm_executable =
canvas_font_size = 8
canvas_default_size = 1280, 1024
**************************************


What to I change? Is it supposed to be:

xterm_executable = "

or what?

I am very paranoid modifying system or program files having been burned many time in the past. I am using Ubuntu 20.04.6 LTS if that matters.

Thanks for any help, Larry Wickert

Screenshot png attached.