HTML mode has been removed from Uzbl in favour of using data URI scheme.

Uzblcat was a small perl script that made handling uzbl's HTML mode easy and safe.

uzblcat *.html | uzbl

curl foo.com bar.org | uzblcat | uzbl

curl baz.net | BASE_URL=http://baz.net uzblcat | uzbl

You can use the following replacement for with scripts that depended on it.

#!/usr/bin/env python

from sys import stdin, stdout
from base64 import b64encode

stdout.write("uri data:text/html;base64,")
stdout.write(b64encode(stdin.read()))

# vim: set noet ff=unix

In some cases you need to specify to read the config from stdin

./uzblcat < file.html | uzbl-core -c -