diff --git a/docs/images/lib2x-polyline2d-4.JPG b/docs/images/lib2x-polyline2d-4.JPG
new file mode 100644
index 00000000..50c5a4fd
Binary files /dev/null and b/docs/images/lib2x-polyline2d-4.JPG differ
diff --git a/docs/lib2x-polyline2d.md b/docs/lib2x-polyline2d.md
index 4d19aa31..f75dec80 100644
--- a/docs/lib2x-polyline2d.md
+++ b/docs/lib2x-polyline2d.md
@@ -34,4 +34,8 @@ Creates a polyline from a list of `x`, `y` coordinates. When the end points are
 	polyline2d(points = [[1, 2], [-5, -4], [-5, 3], [5, 5]], width = 1,
                startingStyle = "CAP_ROUND", endingStyle = "CAP_ROUND");
 
-![polyline2d](images/lib2x-polyline2d-3.JPG)
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+![polyline2d](images/lib2x-polyline2d-3.JPG)
+
+About `joinStyle`:
+
+![polyline2d](images/lib2x-polyline2d-4.JPG)
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