In case you missed the announcement post on mt.com, yesterday evening we released Movable Type 4.23. Much thanks to the community members who submitted bug reports and code patches that contributed to this release. More details can be found on the change log, or you can just use the following direct download links to get MTOS 4.23:
Please note that this is a mandatory security upgrade due to the fixes for XSS vulnerabilities that it includes.
Please note that this is a mandatory security upgrade due to the fixes for XSS vulnerabilities that it includes.


Michael
December 4, 2008 1:27 AM | Reply
Installing MT 4.23 downgraded the StyleCatcher plugin from 2.2 to 2.1, breaking the Sandbox template set plugin. Reinstalling the 2.2 version of the plugin, seems to have restored the lost functionality.
http://plugins.movabletype.org/stylecatcher/
Abby Van Buren
December 15, 2008 4:15 PM | Reply
I just upgraded my companies blog and had no problems, it was as smooth of a process as upgrading can be!