http://breezewiki.catsarchywsyuss6jdxlypsw5dc7owd5u5tr6bujxb7o6xw2hipqehyd.onion/minecraft/wiki/Java_Edition_removed_features
When a map was generated, most exposed water blocks would be frozen into ice. The water did not freeze completely near gravel beaches. The third element was a decrease in the spawning rate of passive mobs.