docs/userguide: fix the for_window syntax

diff --git a/docs/userguide b/docs/userguide
index e38f0d123c9546c1d233fd9637a20dd4b8055b88..184848aa2526111f891f6a7a960b9724d9e09bb8 100644 (file)
--- a/docs/userguide
+++ b/docs/userguide
@@ -431,7 +431,7 @@ change their border style, for example.
 
 *Syntax*:
 -----------------------------
-for_window [criteria] command
+for_window <criteria> command
 -----------------------------
 
 *Examples*: