Property List _Set not working when field with same name as property exists

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Godot version

4.0 beta8

System information

Windows10, AMD Ryzen 9 3900XT, RTX3070, Vulkan

Issue description

When making a conditional property, by overriding _get_property_list and _set and _get, the inspector is not updated unless you de- and reselect the node, when you have a field (in C# it does not matter whether it is public or private) that has the same name as something that the propertylist contains. E.g. the following does not work:

@tool

extends Node2D


var ShowSecondProperty : bool


func _get_property_list():
	var ret: Array = []
	ret.append({"name": "ShowSecondProperty", "type": TYPE_BOOL})
	if(ShowSecondProperty):
		ret.append({"name": "SecondProperty", "type": TYPE_BOOL})
	return ret

func _set(property, value):
	if(property == "ShowSecondProperty"):
		ShowSecondProperty = value
		notify_property_list_changed()
		return true
	return false
	
func _get(property):
	if(property == "ShowSecondProperty"):
		return ShowSecondProperty
	return null

but renaming the field to _showSecondProperty would. So, there must be no field in the class that has the name "ShowSecondProperty" which is added to the PropertyList.

I attached a replication project that demonstrates this behavior for both C# and GDscript.
This might or might not be related to #43238.
I am not entirely sure whether this is a bug or just the lack of an error message or hint of some kind, but I just lost two hours of my time and a bit of sanity figuring this out.

Steps to reproduce

Append the script to a Node and observe the behavior when you modify the script's properties in the inspector.

Minimal reproduction project

UpdatePropertyList.zip

[ianling]

In case anyone comes across this and wants a simple workaround: prefix your property name with a slash and handle it in the _get and _set methods: #56614 (comment)

[KoBeWi]

You can't use _get_property_list() to add another property of the same name...
_set() and _get() is not called for existing properties, use setters/getters instead.

I guess it can be clarified in the documentation.