Is there a way to change the thickness of the separator lines

Is there a way to change the thickness of the separator lines?

If you don't use the skin the thickness is always 2 pixels. Skin can define other size.

Also separators have margins. Marging can be changed in TLB Settings->Menu->Sizes or in TLB Settings->Toolbar->Sizes

There is a way to accomplish this without using a skin. Uses TLB Settings->Menu->Sizes or in TLB Settings->Toolbar->Sizes to set like a wide margin. Then right-click on the separator and choose Appearance. Change the background color. Result is just about the same as a thicker line.