diff --git a/samples/tcl/snowflake.tcl b/samples/tcl/snowflake.tcl
index 3b50252e58..d31dc5a492 100644
--- a/samples/tcl/snowflake.tcl
+++ b/samples/tcl/snowflake.tcl
@@ -137,7 +137,7 @@ vfit
 
 # add dimension
 explode snowflake v
-vdimension length -length -shapes snowflake_93 snowflake_15 -plane xoy -value 0.001 -dispunits mm -showunits -flyout 70 -label above -color black -text 5 3d sh
+vdimension length -length -shapes snowflake_89 snowflake_15 -plane xoy -value 0.001 -dispunits mm -showunits -flyout 70 -label above -color black -text 5 3d sh
 
 if { [regexp HAVE_GL2PS [dversion]] } {
     puts "You can use command vexport to generate PDF: vexport your_file_path.pdf"
diff --git a/tests/bugs/modalg_6/bug26446 b/tests/bugs/modalg_6/bug26446
new file mode 100644
index 0000000000..8db09c3540
--- /dev/null
+++ b/tests/bugs/modalg_6/bug26446
@@ -0,0 +1,20 @@
+puts "========"
+puts "OCC26446"
+puts "========"
+puts ""
+#####################################################
+# GeomConvert::ConcatC1 produces not expected curve
+#####################################################
+
+pload QAcommands
+
+smallview
+
+restore [locate_data_file OCC26446-c1.draw] c1
+restore [locate_data_file OCC26446-c2.draw] c2
+OCC26446 r c1 c2
+
+donly r
+fit
+
+set only_screen_axo 1