Right-click any of the column headings to see a drop-down list of the available columns. There you can add or remove any to suit you.

The headings (they are actually buttons and can be used to set sorting) can be drag-and-dropped along the toolbar to position them. Grab and drag their edges to set column widths.

F8 will toggle the Message Pane. This is also available in the menu under View|Layout.o, via the Application Menu button, under Options|Layout.

Am still unable to have the pilcrow displayed when i am creating an email to show me tabs, spaces etc ..... Is this not available functionality within the Thunderbird product?

To be clear: The pilcrow symbol ¶, also called the paragraph mark, paragraph sign, paraph, or alinea (Latin: a linea, 'off the line'), is a typographical character commonly used to denote individual paragraphs.18 Apr 2017

Hope you can help

Regards

Colin

I am not aware of any method to display such white space characters in Thunderbird. The nearest it offers, via add-ons, is to view and edit the HTML source directly.

Users who like such things often ask for a "pluggable editor" option, so you can delegate your text editing to your favourite editor that does have such features. Unfortunately, I don't think I can point you to a reliable pluggable editor feature either.