I don't know if this has been posted in the past as I haven't found anything on it. I recently purchased a 2017 Genesis Flashback and after following a video on YouTube was able to get it to load more ROMS onto it. Following the process of using ADB to backup the all.games.ini so it could be edited for the new games, I got curious if I could backup the entire directory. I know someone has created a custom firmware for the 2018 and 2019 versions, and I don't know if this was part of that process or not. I have included a screenshot of the directories found under /system on the flashback. I am wondering if the .apk files found in the apps directory (com.atgames.menu.sega_usa.apk, Genesis-082917.apk, and MasterSystem-082817.apk) could be customized further. Like adding categories to it to organize the games better, or maybe working on the emulation so it runs the games that have issues. Unfortunately while I'm good at tinkering at things, programming and understanding how the files actually work is not my expertise.