I found out that it was moved a little. It’s still on live traffic but you need to click “run whois” on the block you see. For example.
In this screenshot we see an IP we want to block as a network. Click the “run whois” button. (sorry, but no ability to add screenshots on www.remarpro.com forums)
https://s10.postimg.org/8tdv6vrmx/wordfence_customer_screenshot.png
You should see a side panel like the next images shows that includes buttons to block the network.
https://s10.postimg.org/6q3fzazkp/wordfence_customer_screenshot_step_2.png
Unless I’m missing something (correct me if I am wrong) you shouldn’t have to leave the site and use any other tool to do this.
tim