Loading PostCSS "purgecss" plugin failed: loadedPlugin is not a function when using .postcssrc.yml

[jackkemmish]

Hi there, I am trying to use this as part of my postcss config, and we use a yml file to do this.

My current yml set up is:

plugins:
    postcss-normalize: {}
    postcss-inline-svg:
        paths:
            - 'static/svg/'
    autoprefixer: {}
    purgecss:
        content:
            - './templates/**/*.ss'

However on build, I get this error: Loading PostCSS "purgecss" plugin failed: loadedPlugin is not a function.

Can someone shed some light what I might be doing wrong here??

Thanks,
Jack