Sharing one of two monitors in Linux

Hello, Discord team!

I am a teacher of higher mathematics in Russia. Since the beginning of coronavirus pandemia I work online and use Discord to broadcast my lessons. My computer has two screens: one for whiteboard, another for text chat, notes and other auxiliary stuff. When I use Windows system, I can select one screen to share with students, and keep another unseen by them. It is wery convenient to use my monitors this way. 

But when I work in Linux (I have Linux Mint 20 Cinnamon now), there is only one option available - to broadcast both two screens as one large hyperscreen. So it is unconvenient to use live broadcast mode in my work, because students see whiteboard as only a part of their monitors, and see all my auxiliary information in right half of it.

This problem does not look unsolvable, because Skype and OBS Studio allow me to select one screen or another without any problems. And Discord for Windows also allows me to broadcast one screen. 

Please, add ability to broadcast one screen in next version of Discord application for Linux!