Indeed it does not deal with changing the columns displayed because the function to do that is entirely accessible as it is. The point is it makes it much easier to determine what the actual problematic column is without having to jump through all sorts of gyrations to do so. Getting rid of it is a matter of bringing up the Thunderbird column selection dialog and unchecking it. The add-on lets you do the necessary legwork to determine what needs to be moved/removed with far greater ease, which is my point.
Brian - Windows 10 Pro, 64-Bit, Version 2004, Build 19041
A gentleman is one who never hurts anyone's feelings unintentionally.
~ Oscar Wilde