diff --git a/doc/classes/InputEvent.xml b/doc/classes/InputEvent.xml
index d412ce09e2d..ccb5c5400a1 100644
--- a/doc/classes/InputEvent.xml
+++ b/doc/classes/InputEvent.xml
@@ -111,6 +111,7 @@
The event's device ID.
+ [b]Note:[/b] This device ID will always be [code]-1[/code] for emulated mouse input from a touchscreen. This can be used to distinguish emulated mouse input from physical mouse input.