The workaround proposed by @Mikal Houston worked for me, using the swiftshader directory from the chromium browser. On kUbuntu 20.04:
sudo ln -s /snap/chromium/current/usr/lib/chromium-browser/swiftshader /opt/minecraft-launcher/swiftshader
Frambueso
The workaround proposed by @Mikal Houston worked for me, using the swiftshader directory from the chromium browser. On kUbuntu 20.04: