weav supports sharing of iMac laptops using the built in AirPlay support.  Your iMac needs to be on the same network as the conference computer that is hosting weav host. Weav does not support other screen sharing like Miracast or Chromecast. 

1. On your Mac, click  in the menu bar at the top of your screen. 

2. If you don't see , go to Apple  menu > System Preferences > Displays, then select "Show mirroring options in the menu bar when available."

3. Click on the weav conference room

4. Your laptop will be shared on the weav host