[dwaite]

It was common to have to parse below XML (angle bracket counting) to convert each stanza to an XML element, then parse those as separate XML documents.

You'd also have to explicitly turn XML namespace support _off_, since so many systems didn't actually support them. XML defines well-formedness and namespace-well-formedness as two different things, and you didn't want to completely drop communication because the other side was sending a message that didn't meet the more stringent requirement.

Some implementations would figure out ways to incrementally disrupt and extract elements from the DOM - but this would sometimes cause resource leaks due to the design of the W3C DOM itself.

The expat had explicit support for parsing Jabber/XMPP messages very early, and was by far the most often XML component used for making libraries.