Detected when importing recent MediaWiki dumps containing some pages
with script content in plain text format (see Scribunto extension
https://www.mediawiki.org/wiki/Extension:Scribunto ).
Further improvement : modify the MediawikiImporter to prevent processing
revisions whose <model> is not wikitext.
When WikiCode inserted in a peer hosted Blog, Wiki, Messages or Profile
contains relative links (images or any content, hosted in DATA/HTDOCS),
it is more reliable to keep these links relative, especially when the
peer is behind any kind of reverse Proxy.