If you can only share chrome and some apps, that's because you're running Chrome/Discord/Slack/etc in XWayland, hence only having access to other XWayland apps.

If you can only share chrome and some apps, that's because you're running Chrome/Discord/Slack/etc in XWayland, hence only having access to other XWayland apps. Chromium (hence Electron apps) still hasn't made the switch to defaulting to wayland when available, you need a few CLI flags to get proper sharing.