How do I access the "advanced" Highlighter menu without
using the mouse?
You must hold down both the Shift+Ctrl keys when opening the
context-menu, if you are not using the mouse, to access the advanced
Highlighter menu.
For example, on Windows, the normal menu is opened with
the Shift+F10 key combination while the advanced menu is opened with the
Shift+Ctrl+F10 key combination.
Why don't printed webpages show the highlighted colours?
You must enable the "Print background" checkbox in the "Page Setup"
dialog to show the hightlighted colours.
(screenshot)
How do I highlight a column (vertical cells) in a table?
Hold down the Ctrl key and click on the first cell in the table
to select it. Then hold down the Shift key and click on the last cell
in the column which you want to highlight. All the cells in that column
should now be selected. Now right-click on any of those cells and choose
the "Highlight" option.