From Habari Project
The 0.9.1 release provides bugfixes and enhancements for the 0.9 series. Although the update is non-critical, users are encouraged to upgrade to avoid any potential issues.
We changed our translation platform to Transifex. So, if you want Habari in your language, you are more than welcome to join us there. We will create a translator team for you if you request it. You can login with your social network accounts, so no additional registration is required. Habari on Transifex
- Handle deleted user info properly #499
- Fix validate_required FormUI validator for arrays #389
- Add new FormUI validator for array values #23
- Fix latest comments dashboard block 
- Fix merging tags into new tag 
- Fix null values generating bad queries #452
- Fix URL arguments can't be filtered*451
- Fix Publish and Save Buttons No Longer Line Up *456
- Fix Empty areas should not be displayed at all in themes *479
- Changes to the way Flickr sends requests  and 
- Removed leftover code 
- New hook for URL arguments 
- Updated character set detection in the pingback plugin 
- Tagtray is not a core plugin. Removed it's styling rules from core Habari 
Upgrading should be safe and possible without further work. Still, as with any change to a production system, you should backup your database and files.
As with any piece of software issues and enhancement requests remain. For full details see Habari's Issue tracker on GitHub.