Null references not working as intended in Godot 4.3 dev6?

[jktrctt]

Tested versions

Reproducible in 4.3 dev6

System information

Windows 10, Godot 4.3 dev6, Vulcan dedicated

Issue description

In 4.3 dev6, null references to objects that were freed do not work in the same way they did in 4.2. For example, if a variable contains a reference to an object and the object is freed, the statement:
if object_reference != null
no longer returns false.

Steps to reproduce

Run this project in both 4.2 and 4.3 dev6 and you will see that it behaves differently.

Or just run this code in a blank scene with a Node2D in it:

extends Node2D


var reference : Node2D


func _ready():
	reference = $Node2D
	print(reference)
	reference.queue_free()
	

func _process(delta):
	if reference != null:
		print(reference)

Minimal reproduction project (MRP)

MRP.zip

[akien-mga]

This was an intentional change in 4.3, see #73896 and #90513 for details.