sorry it might be a bit late, but you can increase the duration of the built-in one by running this command in terminal:
gsettings set org.gnome.settings-daemon.plugins.media-keys max-screencast-length 600
Replace 600 with the number of seconds you want to be able to record for.
I've been intrigued with this for a while and have found the way to disable Wayland!
Run this command:
sudo nano /etc/gdm3/daemon.conf
and find #WayLandEnabled=false
Remove the #. Then
Ctrl + X, then click y, then enter.
Restart your computer.
Done! You are now using DirectX again. All your screen recorders should now work. The built-in screen recorder (Ctrl+Alt+Shift+R) should be a LOT smoother now as well for old laptops.
Shift-Ctrl-Alt-R
is sufficient? See askubuntu.com/a/1013746/504066 (Loosely related question, but shows the shortcuts)