I found the cause of this problem, nodecanvas failed to serialize LayerMask filed with using LayerMask.NameToLayer() .
If I initialize a LayerMask filed in class like : LayerMask lm = 1 << LayerMask.NameToLayer(“a”) | 1 << LayerMask.NameToLayer(“b”),nodecanvas serialize it failed, because I can not find it in json file.
Maybe it’s not the new version problem, but it’s very hard to debug.