Click on long tic mark to restore default text size in Panel Menu

As one grows older, vision and manual dexterity may deteriorate. If it does, it may become a bit difficult to grab the small arrowhead and place it accurately on the long mark indicating the default on the text size slider at the top of the panel menu. It would be much easier to be able to click (or double click) on the long default mark to have the size automatically return to the default with the arrowhead perfectly placed.