WFTB gives you the ability to edit each block element M/W/W (Man, Woman, Wedding) + Links of your family tree.
A basic setting is set by default when editing a template.
If you want to keep it, you don't have to do anything.
To modify the appearance of block elements separately, simply click on one of the M/W/W buttons in the menu and then click on the "Block" tab to access the settings.
You can then, for the chosen element, adjust the three parameters (thickness + outline color, fill color).
For links (father, mother, child) there are only two parameters (thickness and color).
Intended to give free rein to your creativity these features allow you to obtain a very precise result.