Applications need to be open to share them. If the application isn't open, it won't appear as an option to share. Go to the Share Application/Screen button. Spacebar or select Share Application/Screen button to open an operating systems dialog window or Share Application/Screen panel in Collaborate.
Click on the Privacy Tab and locate Screen Sharing on the left. Check the checkbox to allow Google Chrome or Firefox to share your screen. More information about this issue can be found at this link. You may need to reload your Collaborate session for the change to take effect.Sep 13, 2020