Column layout of the message list;

This feature allows you to choose the order of the columns in the message list and to add or remove columns.

To use it, first select the message list or folder tree then press Alt+c;
The Column layout" dialog appears. It consists of the list of columns as well as the "Help", "columns" and "Close" buttons. The "columns..." button showsthe native Thunderbird "Choose columns to show" menu
When you are in the column list, the following keyboard shortcuts are available:
• Left arrow: displays the menu named "Choose the columns to display". This shortcut corresponds to the "Columns..." button;
• Space: to move the selected column, press Space then go to another column and press Space again to place the column there. This operation is similar to a cut and pasteoperation ;
You also have these direct movement shortcuts:
• Control + up arrow or Control+down arrow: move the selected column up or down by one position ;
• Control + Home or End: moves the selected column at the top  or bottom of the list;
• Control + Previous page or Next page: raises or lowers the selected column by three positions ;
Columns are moved by dragging and dropping with the mouse. A one-millisecond beep occurs for every 10 mouse cursor  moves ;
When the "Choose columns to show" menu is present, you have the following new keyboard shortcuts:
• Right arrow: displays the "Column layout" dialog ;
• Space: checks or unchecks the column selected in the menu ;
With the left and right arrows, it is therefore very easy to switch between the column choice menu and the dialog for their layout.