Updated documentation to visible property in CanvasItem, closes #20809

doc/classes/CanvasItem.xml

@@ -497,7 +497,7 @@
 			<return type="void">
 			</return>
 			<description>
-				Show the CanvasItem currently hidden.
+				Show the CanvasItem currently hidden. For controls that inherit [Popup], the correct way to make them visible is to call one of the multiple popup*() functions instead.
 			</description>
 		</method>
 		<method name="update">
@@ -531,7 +531,7 @@
 			If [code]true[/code] the parent [code]CanvasItem[/code]'s [member material] property is used as this one's material. Default value: [code]false[/code].
 		</member>
 		<member name="visible" type="bool" setter="set_visible" getter="is_visible">
-			If [code]true[/code] this [code]CanvasItem[/code] is drawn. Default value: [code]true[/code].
+			If [code]true[/code] this [code]CanvasItem[/code] is drawn. Default value: [code]true[/code]. For controls that inherit [Popup], the correct way to make them visible is to call one of the multiple popup*() functions instead.
 		</member>
 	</members>
 	<signals>