` - but NOT having the possibility to use any other assets/files/URIs) new Mutation(MutationMode::Set, Directive::StyleSrcAttr, SourceKeyword::unsafeInline), // allow `data:` images new Mutation(MutationMode::Extend, Directive::ImgSrc, SourceScheme::data), // limits `` element to be use just for same-origin URIs new Mutation(MutationMode::Set, Directive::BaseUri, SourceKeyword::self), // Allows to fetch media assets from YouTube and Vimeo and their associated CDNs, // to be embedded in an `