manual: install: mention how to discover plugged in device.

docs/manual/src/install.rst

@@ -71,6 +71,13 @@ If these instructions don't work for you, please `file a bug <file-a-bug_>`__ so
         $ glasgow --version
         $ glasgow build --rev C3 uart
 
+    Plug in your device and confirm that it is discovered by running:
+
+    .. code:: console
+
+        $ glasgow list
+        C3-20230729T201611Z
+
 .. tab:: Windows
 
     You will need to have `git <git-win_>`__, `Python <python-win_>`__, and `pipx`_ installed.  To install git and Python, follow the instructions from their respective pages. To install pipx, run:
@@ -108,6 +115,13 @@ If these instructions don't work for you, please `file a bug <file-a-bug_>`__ so
         > glasgow --version
         > glasgow build --rev C3 uart
 
+    Plug in your device and confirm that it is discovered by running:
+
+    .. code:: doscon
+
+        > glasgow list
+        C3-20230729T201611Z
+
 .. tab:: macOS
 
     You will need to have `pipx`_ installed. If you haven't already, install `Homebrew <https://brew.sh/>`_. To install pipx, run:
@@ -145,6 +159,13 @@ If these instructions don't work for you, please `file a bug <file-a-bug_>`__ so
         $ glasgow --version
         $ glasgow build --rev C3 uart
 
+    Plug in your device and confirm that it is discovered by running:
+
+    .. code:: console
+
+        $ glasgow list
+        C3-20230729T201611Z
+
 .. tab:: FreeBSD
 
     You will need to have `pipx`_, `Yosys`_, `nextpnr`_, and `icestorm`_ installed. To install these packages, run:
@@ -182,6 +203,13 @@ If these instructions don't work for you, please `file a bug <file-a-bug_>`__ so
         $ glasgow --version
         $ glasgow build --rev C3 uart
 
+    Plug in your device and confirm that it is discovered by running:
+
+    .. code:: console
+
+        $ glasgow list
+        C3-20230729T201611Z
+
 .. _git-lin: https://git-scm.com/download/linux
 .. _git-win: https://git-scm.com/download/win
 .. _python-lin: https://www.python.org/downloads/source/