postcss plugin tailwindcss requires postcss 8. migration guide for end-users
yarn remove tailwindcss postcss autoprefixer
yarn add tailwindcss@npm:@tailwindcss/postcss7-compat @tailwindcss/postcss7-compat postcss@^7 autoprefixer@^9
# For zsh:
yarn add "tailwindcss@npm:@tailwindcss/postcss7-compat" "@tailwindcss/postcss7-compat" "postcss@^7 autoprefixer@^9"