dataUriMatcher function
Implementation
CustomRenderMatcher dataUriMatcher(
{String? encoding = 'base64', String? mime}) =>
(context) {
if (context.tree.element?.attributes == null ||
_src(context.tree.element!.attributes.cast()) == null) return false;
final dataUri = _dataUriFormat
.firstMatch(_src(context.tree.element!.attributes.cast())!);
return dataUri != null &&
dataUri.namedGroup('mime') != "image/svg+xml" &&
(mime == null || dataUri.namedGroup('mime') == mime) &&
(encoding == null || dataUri.namedGroup('encoding') == ';$encoding');
};