Module build failed - TypeError: this.exec is not a function

[neilf184]

Hi,
I'm attempting to upgrade from webpack 4 to webpack 5 in a Symfony project (symfony webpack-encore 0 to symfony-webpack 1). My app is failing to build (using npm build dev) with the following error:-

Module build failed (from ./node_modules/modernizr-loader/index.js):
TypeError: this.exec is not a function
at Object.module.exports (/var/www/dev2.yourdolphin.com/node_modules/modernizr-loader/index.js:24:26)

modernizr v3.12.0
modernizr-loader v1.0.1