npm WARN deprecated [email protected]: core-js@<3 is no longer maintained and not recommended for usage due to the number of issues

Solution 1:

Indeed the issue was with cache. npm clean-install worked.

Solution 2:

Try:

npm cache clean --force
npm install -g @angular/cli@latest

Solution 3:

It's a npm cache problem. Go to the path:

• Windows: %AppData%/npm-cache
• Linux/OSX: ~/.npm

and delete its content. Then open your console in administrator mode and execute the npm install command again

Solution 4:

You should update the version of core-js to version above 3. npm install --save core-js@^3

You may also update the outdated packages using npm update [-g] [<pkg>...]

Solution 5:

I observed this warning message within a Vaadin project with Vaadin 14.1.3 after switching from dependency com.vaadin.vaadin to com.vaadin.vaadin-core. The warning was gone after these steps:

1. delete package-lock.json
2. execute mvn clean
3. execute mvn update