I am guessing you need to press F8 on your keyboard.

TRIED THAT BEFORE I GOT THIS WHAT DO I DO WITH IT ?

I turn my head to the left so it is on it's side and I see an image that I recognize not at all.

I used the image to search google and got this from their AI

The image shows the "Project" menu on a Windows computer, which is used to manage how the screen is displayed. This menu is typically accessed by pressing the Windows key + P. The options available are:

• PC screen only: Displays the image on the primary computer screen.
• Duplicate: Shows the same image on both the computer screen and a connected secondary display.
• Extend: Expands the desktop across both the computer screen and a connected secondary display, allowing you to use them as a single, larger screen.
• Second screen only: Displays the image only on the connected secondary display.

I have no idea how pressing F8 in Thunderbird gets you a windows menu that is normally accessed using the Windows key + P unless you8 have some software installed that allows you to change windows shortcut keys or your keyboard is broken.

However I can now see the menu you posted by pressing the Windows key+P on my computer keyboard. As I said however I have no idea how you got there with the instructions you were given.

I don't understand it myself... kinda like the wizard of oz... who couldn't bring the balloon back for Dorothy It just started after and auto upgrade... beta ?

All I can suggest is try the menu approach.

Alt key + V then l then m

Thanks for the hint... 4th column reading pane ... nope ...

Ok, I have been assuming you are talking about the message pane.

tre settngs for which appear on the menu bar here,

or on the app menu (☰)

I have assumed this because I have no idea what this fourth column is. The reading pane is show here https://support.mozilla.org/en-US/kb/how-change-thunderbird-layout in the vertical view as the third pane, followed by the today calendar pane. Since that article was written a places pane has also been added.

So the default in a vertical view is really 5 columns with the reading pane in this layout being the one with the mauve and purple showing a default no message selected page. Please correct me it I am wrong and you are talking about something else.

Vertical view solves my issue...Thanks Matt