I have loaded 18.04 onto an old HP Pavilion 23", which doesn't have a display out. I have a USB display adapter, which is working well and I have a Samsung 32" TV that I'm using as a monitor.
When I go to screen display it shows the second monitor as a Samsung 7" and only allows the scale to be 100% or 200%.
I want to reduce the scale to about 50% but cannot find anywhere to do that.