Here is a little fix, waiting for manjaro team to release last mesa version.
wget https://archive.archlinux.org/packages/m/mesa/mesa-20.1.8-1-x86_64.pkg.tar.zst
sudo pacman -U mesa-20.1.8-1-x86_64.pkg.tar.zst
Hope that will help you too.
Have fun 
Here is a little fix, waiting for manjaro team to release last mesa version.
wget https://archive.archlinux.org/packages/m/mesa/mesa-20.1.8-1-x86_64.pkg.tar.zst
sudo pacman -U mesa-20.1.8-1-x86_64.pkg.tar.zst
Hope that will help you too.
Have fun