GDLauncher Version: 2.0.20
Error: neoforge manifest does not contain loader '21.1.83'

I try to download the latest version of the "Opolis Inc" modpack and I continually get this error. Curseforge doesn't have this issue, but I have a vast preference for GDLauncher over Curseforge, and would like the neoforge manifest to be updated sooner than later.