Adobe should have explained in bold letters that proto files cannot be shared or viewed by others (clients).
First of all, a client that gets a .pro extension can't do anything with it, which means wasting my time teaching each client how to change the extension to zip or even worse, explaining clients on how to see the extension in Windows.
Second, most clients open the HTML files directly from the ZIP folder which doesn't render the CSS (the css path gets broken). So now I need to explain to clients how to use ZIP.
Third, If I don't let clients download the .pro (which is a good idea for now), all they can see in the "cloud" is a cropped page view and not the entire height of the page. And no, clicking on the magnifying glass doesn't fix the issue. A long page will be cropped.
Adobe, I hope you won't ask for upgrade fees this time round.