This article is a stub. One of us will have to go and actually verify things.
Freeze is a clone - and editor - of ZZT and Super ZZT developed by Isaac Brodsky in Java.
The initial iteration, Freeze 1, was being developed in 2011 and achieved partial compatibility.
The second iteration, Freeze 2, was being developed in 2020 and aims at much higher compatibility, being inspired by research found in the Reconstruction of ZZT.