Use of Uint8Array constructor in Blob.js not supported on older browsers

[asacordex]

Seems like Uint8Array constructor is not supported in older browsers such as safari 10 and older. Would be great if the script checked if this constructor exists, and if doesn't exist used just an Array instead of Uint8Array.

Ref: https://caniuse.com/#search=Uint8Array

[jimmywarting]

I believe it already dose that