In order to use this generator efficiently, I strongly recommend a latest version of any web browser.
Works best with google chrome and firefox.
You may test it but never ever use the generator online for production. Instead, download the codes in your computer and run offline. In this case, offline meaning that cut the internet during the generation process.
Once you have generated enough wallets, keep them in a secure usb thumb drive and delete from your computer.
Paper wallets are not different from your actual wallet so treat them as such.
If you find any vulnerability, please report it to me through issues section or send email directly.
I will regularly update the libraries used in the wallet generator.