Where is the "Virtual Pixel Mode" option? I'm searching for an option to make shown wireframe thicker. I found one solution there What is the setting that changes wire frame thickness?, but I can't find that Virtual Pixel Mode switch in my System options.

Upd: Another option (Line width) seems do something similar , but it changes some GUI parameters and vertex sizes too.

How to change edge widths only or is there a way to change back the GUI lines and Vertex sizes without changing edge widths? Thank you.
This setting has been renamed in the most recent builds (also Blender 2.80 series) to Line Width. You can find it in the Interface section. Possible settings are Thick, Thin or Auto: