Preview of the 4.3 API

[migueldeicaza]

Hello folks,

While Godot 4.3 has not been released yet, the team has announced that Godot 4.3 is feature complete, so I did an initial pass at upgrading the API bindings, they currently live in the 4.3 branch, and I will keep updating until the official launch.

[migueldeicaza]

I am tracking some of the API updates that are nice-to-have but not mandatory yet here:

#460