The "cover mod" for Snes9x GX isn't an official feature of the standard emulator. Instead, it refers to a of Snes9x GX that adds box art cover support to the ROM selection screen. Below is a general guide for installing and setting it up.
Find and download custom cover art for your favorite SNES games. You can search online for "SNES cover art" or "SNES9x GX cover mods" to find various repositories and forums where users share their custom cover art. Make sure to download images in a suitable format (e.g., PNG or JPEG). snes9x gx cover mod install
For best results, use lowercase .png files and avoid special characters. The "cover mod" for Snes9x GX isn't an