bonbon@debian:/var/www/hint_ui$ yarn install
yarn install v1.9.4
info No lockfile found.
[1/4] Resolving packages...
warning istanbul-instrumenter-loader > istanbul-lib-instrument > babel-generator > babel-runtime > core-js@2.6.11: core-js@<3 is no longer maintained and not recommended for usage due to the number of issues. Please, upgrade your dependencies to the actual version of core-js@3.