the set of allowed plaintext file types.
Multiple such `<xslt:template>` elements may be provided in a single
parser, for example if the parser supports multiple media types.
+Alternatively, you can set the `@书社:supported-media-types` attribute
+ on the root element of the parser to override media type support
+ detection.
It is **strongly recommended** that all templates in parsers other than
those described above be namespaced (by `@name` or `@mode`), to avoid