If the issue is technical and you’re still having issues can you please try the following:
Try restarting your computer?
Sign out and then back in to the extension. Here’s a quick video that demonstrates how to do that.
Also if you’re seeing any “Failed to capture…” or “Failed to start recording” error messages please try the following:
Switch your "Hardware Encoding" settings on the extension’s Options page. Here's a very quick video that demonstrates how to do that.