diff --git a/inventory/templates/testing.html b/inventory/templates/testing.html
index 2b22eda..b4c9076 100644
--- a/inventory/templates/testing.html
+++ b/inventory/templates/testing.html
@@ -240,9 +240,12 @@ scheduleSnappedGridSize();
 function isFiniteNum(n) { return Number.isFinite(Number(n)); }
 
 function sanitizeShapes(list) {
+    const allowed = ['rect', 'ellipse', 'line'];
+
     return list.filter(s => {
         if (!s || typeof s !== 'object') return false;
-        if (!['rect','ellipse','line'].include(s.type)) return false;
+        if (!allowed.includes(s.type)) return false;
+
         if (!s.color) s.color = '#000000';
 
         if (s.type === 'line') {