I just upgraded my project from 2020.3.35 to 2021.3.4 and now when I select a terrain my editor lags a lot in a way it is impossible to do any actions such as: paint details, smooth terrain, set height, etc.
It usually happens after 5 min of my editor opened. Before those 5 min it works fine, and the lag always come when selecting the terrain even if I’m not doing any action.