Error: Node Sass version 5.0.0 is incompatible with ^4.0.0.

C++
with npm =>
1.npm uninstall node-sass
2.npm install [email protected]
with yarn => 
1.yarn remove node-sass
2.yarn remove [email protected] npm =>
1.npm uninstall node-sass
2.npm install [email protected]
with yarn => 
1.yarn remove node-sass
2.yarn add [email protected] npm =>
1. npm uninstall node-sass
2. npm install [email protected]
with yarn => 
1. yarn remove node-sass
2. yarn add [email protected]

// ^ Update to MR J's postSolution
1 Uninstall node-sass
npm uninstall node-sass

2  use sass by:
npm install -g sass
npm install --save-dev sass
$ npm uninstall node-sass
$ npm install [email protected]

# Or, if using yarn (default in newer CRA versions)

$ yarn remove node-sass
$ yarn add [email protected] uninstall node-sass
npm install [email protected]
Source

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