PostCSS plugin that allows to use html entities inside css content property.

.foo:after {
    /* Input example */
    content: '×'
}

.foo:after {
    /* Output example */
    content: '\d7;'
}

NPM:

npm i postcss-content-entity

Yarn:

yarn add postcss-content-entity

and use it with post css

postcss([ require('postcss-content-entity') ])

See PostCSS docs for examples for your environment.