Linux
MC 1.20.1
QUILT 0.25.0
Unable to read /.minecraft/mods/ghost.jar as a zip file: only DEFLATED entries can have EXT descriptor <mods>/ghost.jar

it has been running fine before i put in my addon
idk what is causing it but i would prefer to continue using quilt, it was the base modpack i was working with and i dont wanna have to bother switching it to fabric in case it just doesnt start working as is when i do

The issue should now be fixed in the web app. You can either re-export your draft, or extract & recompress the jar with a command like jar cvf ghost.jar . within the extracted directory.