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install yarn ubuntu 20.04

sudo apt update
sudo apt install yarn

ubuntu 20.04 install yarn

#Yarn versions prior to 2.0. Install via npm (recommended).
#may require sudo
npm install --global yarn
#Yarn 2 and later may require sudo
npm install -g yarn
#Check installation
yarn --version

install yarn ubuntu 20.04

How to Install Yarn on Ubuntu 20.04 | Linuxize
sudo apt update
sudo apt install yarn