In order for Genesys Cloud to connect a sharer’s screen to the correct agent, a screen share security key must be sent from the sharer to Genesys Cloud. 

• For screen share with voice, the sharer types in a security key that the agent verbally communicates. Your web developers must place this security form on your website.
• For screen share with web chat, web chat sends the security key behind the scenes after the sharer accepts the screen share request from the agent. The agent does not need to verbally communicate the security key, and the sharer does not need to type the key anywhere. However, your web developers still need to configure web chat to work with screen share. 
  
  Note: Web chat with screen share does not support pop-up chat in a new window. For web chat with screen share, you can use either embedded chat, or open chats in a new tab in the same window. 

For directions about how to implement both scenarios, see the Developer Center article about screen share.