Read the official Contao announcements.
TYPOlight 2.4.6 is available
by Leo Feyer – Announcements
TYPOlight version 2.4.6 is available. The new build includes some new features and another mbstring workaround that should allow to run TYPOlight even on those servers that do not support Unicode regular expressions. We are still waiting for dfGallery to be completed before TYPOlight 2.5 is released. The new build will be available on github.com, since a few people are still having issues updating from version 2.4.0.
Download this release from github.com.