How to create separators in an enum popup without warning?

Previously you could create separators in an enum popup using this multiple times:

[InspectorName("")]

like so:

public enum ImageResolutionType
{
	[InspectorName("Game Screen")]
	Game,

	[InspectorName("1080p (1920 x 1080)")]
	Resolution_1080p,
	
	// separator in enum popup
	[InspectorName("")]
	SEPARATOR_01,

	[InspectorName("Icon (128 x 128)")]
	Resolution_Icon_128,

	[InspectorName("Icon (256 x 256)")]
	Resolution_Icon_256,

	// separator in enum popup
	[InspectorName("")]
	SEPARATOR_02,

	[InspectorName("Cubemap (128)")]
	Resolution_Cubemap_128,

}

However that gives a warning now:

Enum ImageResolutionType has multiple entries with the same display name, this prevents selection in EnumPopup.

Is there a new way for creating separators?

Also, why would the same name prevent selection? The selection should be based on an id, not on the name.