Try setting utf8_mode=1

vm/src/sysmodule.rs

@@ -125,7 +125,7 @@ impl SysFlags {
             hash_randomization: settings.hash_seed.is_none() as u8,
             isolated: settings.isolated as u8,
             dev_mode: settings.dev_mode,
-            utf8_mode: 0,
+            utf8_mode: 1,
         }
     }