Better fix for null dereferencing issue. Fix initial Color sensor mode (default).

libs/core/input.ts

@@ -68,7 +68,7 @@ namespace sensors.internal {
                 if (info.sensor) return info.sensor._query()
                 return 0
             }, (prev, curr) => {
-                if (info.sensor) info.sensor._update(prev, curr)
+                if (info.sensor && curr !== null) info.sensor._update(prev, curr)
             })
         }