Add slight clarification to debugDeterministicCursor (#27898)

packages/flutter/lib/src/widgets/editable_text.dart

@@ -528,8 +528,12 @@ class EditableText extends StatefulWidget {
   /// {@endtemplate}
   final bool enableInteractiveSelection;
 
-  /// Setting this property to true makes the cursor stop blinking and stay visible on the screen continually.
-  /// This property is most useful for testing purposes.
+  /// Setting this property to true makes the cursor stop blinking or fading
+  /// on and off once the cursor appears on focus. This property is useful for
+  /// testing purposes.
+  ///
+  /// It does not affect the necessity to focus the EditableText for the cursor
+  /// to appear in the first place.
   ///
   /// Defaults to false, resulting in a typical blinking cursor.
   static bool debugDeterministicCursor = false;