"Now, at the end, I will stop the 4.3 version, compile the latest version of the tool in a few days in Godot 3.6": ---> As far as I know, Godot 3.x is maintained by the same community responsible for 4.x. All other forks/engine copies also use 95% of Godot 4.x sources. After more than 200 days, I can't confirm this doomsday scenario. See Github; over 300 PRs and issues are still being reported and closed every month.