Free and Open Source Software

Hi all, I'm looking for some Discord alternatives. All I really need is the ability to do voice calls and screen shares. It can be either via DM or channels, I only need to it be able to speak with a few friends that'd be open to moving over. I've tried Matrix/Element but there doesn't seem to be a screen share function. There's Teamspeak but I don't think that's FOSS nor does it support screen shares as well. Any other options? Basically just voice calls and screen shares is all I need, I couldn't care about channels or servers or whatever other functionalities Discord has put into their app. Thanks!