What is a one-sentence summary of the following article?
WhatsApp Web is supported in the latest versions of Chrome, Firefox, Opera, Safari and Edge. To do this, you will have to open WhatsApp on your phone, and scan the QR Code on your computer screen from your phone. If you need help linking your account to WhatsApp Web, this article will guide you through the process. This is your Menu button, and it's located to the right of your profile picture in the upper-left corner of your screen. If you have a conversation opened, you will see two different ⁝ buttons on your screen. Tap on the Menu button at the top of your Chats menu; not the one in the upper-right corner of the opened conversation. Your Menu options and Conversation options will be different.  This will open up a list of all the contacts you have blocked.  This is the green button, and it will unblock this contact. This person will now be able to call you and send you messages on WhatsApp.

Summary:
Go to WhatsApp Web in a browser of your choice. Link your WhatsApp account to WhatsApp Web. Tap the ⁝ button at the top of your Chats menu. Tap Settings from the menu. Tap Blocked. Tap on the name of the contact you want to unblock. Tap Unblock in the pop-up.