@Override
    public void parse(InputStream stream, ContentHandler handler, Metadata metadata,
                      ParseContext context) throws IOException, SAXException, TikaException {
        //based on: https://mastodon.social/@Ange/110027138524274526
        IOUtils.skipFully(stream, 12); //header
        IOUtils.skipFully(stream, 2); //version
        IOUtils.skipFully(stream, 4); //flag1 04000000
        IOUtils.skipFully(stream, 4);//reserved ffffffff
        IOUtils.skipFully(stream, 4);//flag2 000006F0
        // do something with this?  If so, use readUInt
        // long datasize = LittleEndian.readUInt(stream);
        IOUtils.skipFully(stream, 4); //datasize
        long zlibOffset = LittleEndian.readUInt(stream);
        IOUtils.skipFully(stream, 4);//flag
        IOUtils.skipFully(stream, 4);//uncompressed size
        IOUtils.skipFully(stream, 4);//don't know

        IOUtils.skipFully(stream, zlibOffset);
        XHTMLContentHandler xhtml = new XHTMLContentHandler(handler, metadata);
        xhtml.startDocument();
        EmbeddedDocumentExtractor ex = EmbeddedDocumentUtil.getEmbeddedDocumentExtractor(context);
        try (InputStream payload = new DeflateCompressorInputStream(stream)) {
            try (POIFSFileSystem poifs = new POIFSFileSystem(payload)) {
                OfficeParser.extractMacros(poifs, xhtml, ex);
            }
        }
        xhtml.endDocument();
    }
ActiveMime is a macro container format used in some mso files.  See, e.g.
<a href="https://mastodon.social/@Ange/110027138524274526">Ange's toot</a>.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-microsoft-module/src/main/java/org/apache/tika/parser/microsoft/activemime/ActiveMimeParser.java