Non exhaustive list of changes:
- various security fixes (#2449, #2450, #2451, #2456),
- Add new HOOK to reduce rights of the core by plugin (#2198),
- Fix some translations requiring php-gettext (#2316),
- Fix link with closed tickets (#2389),
- Precisions adding user in sub entity (#2372),
- Fix past tasks display on planning view (#1389),
- Fix ticket reopening issue (#2412).
- ...
See changelog for details.