Okay so for whatever reason, turning Freesync on and off a bunch of times from the OSD and then replugging works until the next reboot, so I’ve dumped the working EDID and I’m trying to figure out how to load it at boot (but I’m not having much luck).
For reference, the monitor is a Samsung LC24RG50.
Edit: Got the EDID loaded, KDE says it’s supported, but VRRTest doesn’t really seem to do anything.