As per https://github.com/robinweser/inline-style-prefixer/issues/159#issuecomment-470307093 the prefixing for [backgroundClip](https://github.com/robinweser/inline-style-prefixer/blob/master/modules/plugins/backgroundClip.js) is applied to the value rather than the property.
As per #159 (comment) the prefixing for backgroundClip is applied to the value rather than the property.