vRA 8 embedded vRO cannot use let when defining variable

I'm currently using vRA7.X and start testing vRA8.

First of all, I could see many enhancement on vRA8 and really exciting to explorer around new features.

So, What I want to share here is new vRO has code suggestion and realized its now allow let/const to define variables.

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But when I use "let" in my code, it will always give me below syntax error and cannot use it.

missing ; before statement (script#XX)

On the other hand, const has no validation issue but its behaviour is not as usual javascript.

try{

    const testConst = "This is const string";

    System.log(testConst);

  testConst = "cannot change!!"

    System.log(testConst);

}catch(e){

    System.log(e);

}

This result should throw exception but output was like this and no error.

2019-11-18 17:33:34.000 +00:00INFO This is const string

2019-11-18 17:33:34.000 +00:00INFO This is const string

I am not sure if this is bug but hope this will fixed in next release.

BTW, I have setup my environment using with vra-lcm-installer-14878991.iso.

Thanks,