@E3L1 Not really, the packages you mention are alive and well on Raspbian Buster and that's not the reason RetroPie doesn't support yet fully the PI4.
Care to share a reference to the quote you posted ?
you need to modify the system.sh script in the /scriptmodules/ folder in the setup directory. As long as you have all debian package repositories, you just need to change line 160 to __os_debian_ver="8".
This is the right fix but needs explained slightly better. I think it's funny the other people that replied with vague explanations but still took the time to comment that they knew what to do. For most (and me) I guess we prefer figuring out these things on our own, but many people just want good help. Not everyone is a long-time Linux user. Even more so, less people code but still want to enjoy nice things.
I looked through the code. There might be another better way to do this- but at least this works. Nano or use your fav editor /RetroPie-Setup/scriptmodules/system.sh and do a CTRL+W to search for (it's at the end of the function get_os_version):
Comment that out with a # at the start of the line, and make a new line beneath it. In the new line type __os_debian_ver="8". This will run through all the checks and ignore them in the end, setting your os version to one that's "supported". Not sure if you need to match the spacing in bash, I think it's only a python thing (someone correct me). This will look like:
# error="Unsupported OS"
Run the retropie_setup.sh script in the main RetroPie-Setup folder as normal. This worked for me but the install is taking forever (over 30 min so far easy). Will update if I need to do anything else. As I couldn't find a better solution anywhere online to this problem, I hope this helps!
Yeah I'm thinking it might just be best to start from scratch and be done with it. I'm just hoping I can put my roms back on it. I do have a back up on my computer but I can't access my roms individually, I'm still learning how this stuff goes but might have to start over on that which is too bad cause I had over 5000 games...