This list is still in preparation; 2.5.12 has not yet been released.

WHAT'S CHANGED SINCE 2.5.11

2.5.12 is a bugfix release. It is expected to be the final release in the 2.5 series.

Server / General

Vision-providing bases, such as buoys, could in some circumstances remove visibility from tiles, perhaps preventing the owner's cities from working them, in the presence of autosettlers. HRM#797698 HRM#781551
When a unit such as a Leader was cargo on a transport that was lost with its home city, it could be 'saved' by teleporting to the site of that city. This could leave an illegal stack of non-allied units on the same tile (Leader and city's conqueror), and prevent the Leader teleporting to a more distant, safe city. HRM#761808
A few resources could be added to the map even when none were requested. HRM#763879
Global warming and nuclear winter had a small chance of occurring even when the client displayed the chance as 0%. HRM#763882
Cities produced pollution slightly too often. HRM#763881
When gaining free Future Techs (for instance from Darwin's Voyage), some messages showed the wrong Future Tech number. HRM#761977
Historians were never reporting on the "LARGEST Civilizations" (with the most citizens), by mistake. HRM#763883
Historians failed to take angry citizens into account when reporting on the "HAPPIEST Civilizations". HRM#763884
The end-game score for an arrived spaceship included population in habitation modules that weren't actually attached to the spaceship at launch. HRM#757442
Fix a possible network protocol warning when units are starving. HRM#661865

In rulesets which allow capturing units, it's no longer allowed to capture a transport which is carrying units. (Previously this was allowed, but left the game in a broken state.) HRM#772516
Fix longstanding bug in rulesets with 129 or more unit types; if any of the later units was an upgrade or conversion target, the client would not allow the action. HRM#763984
In rulesets with nation-specific starting units, care is now taken to place them on tiles they can exist on, and clear any huts from their tile. HRM#767129
Rulesets which defined a unit type without any tech_req could crash the server, rather than giving an error message. HRM#816374
Rulesets which used default/nationlist.ruleset could not define a default_government outside the standard set defined by nationlist.ruleset. HRM#764299
Fix inability to use default/nationlist.ruleset in a custom ruleset lacking standard plural-named terrains such as 'Hills'. HRM#827555
Some improvements to unit debugging (/debug unit). HRM#760368 HRM#760370
Coding style clean up to supplied default.lua script. HRM#822189

Fix a rare compression failure which could stop communication between client and server. HRM#746878 HRM#747319
Slightly improved diagnostics for missing sound files. HRM#799291
Tweak format of comments in various output files. HRM#761206
Various internal changes which should only affect developers. HRM#767074 HRM#800781 HRM#801661 HRM#848260

When setting up single-player games, the client's AI level control no longer gets out of sync with the server state. HRM#765061
In the city dialog, clicking on the middle tile to rearrange workers could fail to update the city dialog map display. HRM#736822
(Gtk3) Happiness tooltips from the city dialog could appear in the wrong place. HRM#768105
(SDL) Fix a possible crash on closing the client. HRM#824593

Miscellaneous improvements to in-game text and user documentation. HRM#744655 HRM#744672 HRM#760366
Miscellaneous changes to developer/ruleset docs. HRM#744666 HRM#692480 HRM#741552

See NEWS for older lists of changes.