Ripple paper wallet: is "ripplepaperwallet.com" safe? I've been reading on the internet and I have found several websites for generating Ripple paper wallets: ripply.eu, bithomp.com, gatehub, etc. I'm not sure if these websites are official Ripple websites and trustworthy for generating paper wallets.

So, I'm wondering whether https://www.ripplepaperwallet.com is an official and trustworthy website for generating wallets.

I'm using Windows 8.1 and the latest version of Google Chrome.
Considering the fact it has iframes (e.g ads) in it and they might have access to the parent (e.g http://ripplepaperwallet.com) DOM, I would say that even if it was an open source project (which I have not found any references to) I would say it relies on a third party that is not open source therefore theoretically can be not safe.    

As well, I did not see an offline version of it, which in my opinion is a good practice to verify integrity of paper wallets.