There have been various bug fixes and some notable changes. So let me note the modding-relevant ones.
These are pretty much self-explanatory:
[Change] No longer allow the direct use of MULTI_INSERT in sql_build_array. sql_multi_insert() must be used.
[Change] More restrictive chmod to new files being created. (phpbb_chmod() function mostly by faw)
[Change] Remove NUL-Bytes directly in request_var() for strings and within the custom DBAL sql_escape() functions (MSSQL, Firebird, Oracle) (reported by AdhostMikeSw)
And then there's of course the new features! Here are my favorites:
[Feature] Allow limited inheritance for template sets.
[Feature] Allow setting custom language path through $user->set_custom_lang_path(). $user->lang_path now also do not include the user language, but only the path.
[Feature] Ability to define nullar/singular/plural language entries
And in this release no security vulnerability was needed to be fixed!
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