getDefaultExtensions "html"            = Set.fromList [Ext_auto_identifiers,
                                                       Ext_native_divs,
                                                       Ext_native_spans]
getDefaultExtensions "html"            = Set.fromList [Ext_auto_identifiers,
                                                       Ext_native_divs,
                                                       Ext_native_spans]
getDefaultExtensions "html"            = Set.fromList [Ext_auto_identifiers,
                                                       Ext_native_divs,
                                                       Ext_native_spans]