Could not find plugin “proposal-numeric-separator”

Question

How to fix Could not find plugin \"proposal-numeric-separator\", I get this error when I try to build my React application, I have not ejected the application y

Answer 1

In my case I've got a corrupted node_modules folder. My yarn install simply stopped in the middle by a power surge.

By running:

rm -rf node_modules
yarn

My problem was solved.