I have to use Web apps that present results in a table, which tends to be eye-boggling if you have to read across to match opposite ends of the line without accidentally slipping onto the next line. I'm looking for something that highlights a line on screen in the same sort of way that lots of text editors do, highlighting the line the cursor is on, as per the image. I could start looking at on-screen rulers, but please, does anyone know of a program more like what I'm looking for?
This is a bit like line highlighters from the days of DOS mono LCD laptops

Thanks...