diff --git a/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.py b/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.py
index f87ce27e..de98997f 100644
--- a/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.py
+++ b/extensions/fablabchemnitz/contour_scanner_and_trimmer/contour_scanner_and_trimmer.py
@@ -927,7 +927,7 @@ class ContourScannerAndTrimmer(inkex.EffectExtension):
             isPoly = False         
             isBezier = False
             isPolyBezMixed = False
-            chars = set('aAcC')
+            chars = set('aAcCqQtTsS')
             if any((c in chars) for c in str(path)):
                 isBezier = True
             if ('l' in str(path) or 'L' in str(path)):