scanlines

The option documentation is properly formatted yet

Description: "Render scan lines" Default: 0 Example: 1 Type: boolean

Enable scanlines by setting scanlines to 1. The default is 0. When scanlines are enabled, you will see aliasing effects if your resolution is low (and in window mode). Use fullscreen mode with sufficient resolution and the scanlines effect should look good. There will also be a visible moire pattern when entering menu mode (this is normal). Scanline rendering is done on the CPU, and this may negatively impact emulation speed if you do not have a sufficiently fast CPU.

See also [scanlines_dark], [scanlines_light], [rtg_scanlines].

Source: https://github.com/FrodeSolheim/fs-uae/blob/master/docs/options/scanlines