[undertow-dev] FormParserFactory getting stuck

I'm uploading files as "multipart/form-data" and using the FormParser as follows: FormParserFactory.builder().build().createParser(exchange).parse(nextHandler) Sometimes this works fine, but very often my client shows progress up to a certain percentage complete (monitoring the AJAX request) and then just stops and never kicks to `nextHandler`, leaves the connection just sitting there forever, and the server seems to stop accepting any future connections. Any idea what might be causing this?