migrating angular 4 to angular 6 issue

Question

After migrating my application to angular 6, the application does not build with next mistake.

I don't know exactly from which setting or package could be involved ?

I am using webpack 4.21.0

ERROR in ./src/app/outilsvg/forms.css
Module build failed (from ./node_modules/postcss-loader/index.js):
TypeError: loader._compilation.applyPluginsWaterfall is not a function
    at /home/sancelot/NODEJS/PROJET2/PROJVIDE/node_modules/postcss-loader/index.js:122:43
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:188:7)
ERROR in ./src/styles.css (./node_modules/raw-loader!./node_modules/postcss-loader??embedded!./src/styles.css)
Module build failed (from ./node_modules/postcss-loader/index.js):
TypeError: loader._compilation.applyPluginsWaterfall is not a function
    at /home/sancelot/NODEJS/PROJET2/PROJVIDE/node_modules/postcss-loader/index.js:122:43
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:188:7)

Answer 1

npm outdated pointed that I was using version 1.3.0 instead of 3.0.0 of postcss-loader.

I was using postcss-loader