godot/doc/classes/PopupPanel.xml

<?xml version="1.0" encoding="UTF-8" ?>
<class name="PopupPanel" inherits="Popup" version="4.0">
	<brief_description>
		Class for displaying popups with a panel background.
	</brief_description>
	<description>
		Class for displaying popups with a panel background. In some cases it might be simpler to use than [Popup], since it provides a configurable background. If you are making windows, better check [Window].
	</description>
	<tutorials>
	</tutorials>
	<theme_items>
		<theme_item name="panel" data_type="style" type="StyleBox">
			The background panel style of this [PopupPanel].
		</theme_item>
	</theme_items>
</class>