There should be a base64 decode function available from the UI

The current base64 function allows encoding strings using base64, but there isn’t a function to decode a string. This would quite handy while working with gmail email’s where the HTML comes in base64 format.

I’m currently extracting the HTML from an email and I now have to add a JS code module to decode the base64 coded string which isn’t much of a deal, but it would be quite convenient to set the variable with the decoded string right from the UI.

What about adding a param to the function?