Quote from: siajeen on Today at 10:45:39 AM

Why you dont recommend it?

On the one hand, because of this:

Quote from: webtricks on Today at 12:33:34 PM

It is very easy for websites to log your generated keys with Javacript if you are connected to internet. Moreover, even if you download the webpage and try generating paper wallet in offline mode, there are still many risks. Website may keep the trail of your address in browser and when you are once again connected to internet, such trails may be extracted via cross-website cookies or other methods. One more risk is of wireless printer. Suppose you generated paper wallet in offline mode and printed it via wireless printer. In such case, printer's records will have trail of your paper wallet and it is easy to retrieve that by hacking your printer or other connected devices with printer can also see your printed data.

Roughly 2/3 of network connected printer can be hijacked through the internet. Even if the policy only allows printing within the local network.
This can lead to sending print jobs to the printer which execute Postscript or PJL commands. And this allows an attacker to extract previous printer jobs (if being captured). Accessing a malicious website is enough for that.

And on the other hand, the source code of the website could be manipulated. E.g. using a manipulated RNG, which won't create truly random private keys.
It is not hard to shrink the space to an amount too high for random collisions of different people generating the same private key, but at the same time low enough to be able to bruteforce them.

Additionally, i wouldn't trust any javascript library with sensitive crypto operations.