Bugfixes:
— Fixed loading of electric network of pre 0.12 saves.
— Fixed blueprint building. Blueprints are migrated as long as you load the version 0.12.30 or earlier, existing bluepritns might be off if you resaved in 0.12.31 already.
Scripting:
— Lua interface to create blueprint now expects the entity positions to be relative to center exactly, so in rail-less blueprints, the position 0.0 translates to center of the tile
when the blueprint is built.

Bugfixes:
— Fixed crash when script errors occurs while loading game while in game. (https://forums.factorio.com/23222)
— Fixed that attempting to connect to Factorio 0.12.30 with an old client wouldn’t produce the correct error message. (https://forums.factorio.com/23177)
— Fixed that modded roboports with no charging slots were still considering as charging candidates. (https://forums.factorio.com/23289)
— Fixed that item icon variant for dark background was not used when showing cargo of logistic robots. (https://forums.factorio.com/23286)
— Fixed crash with «Unblock sendto failed: The operation completed successfully.» (https://forums.factorio.com/23206)
— Human readable error notice when multiplayer connection wasn’t successful. (https://forums.factorio.com/23132)
— Fixed that headless server wouldn’t save the map after Control-C. (https://forums.factorio.com/23342)
— Fixed that attacking biters with a mining tool wouldn’t aggro them.
— Improved map download speed when connecting to multiplayer game. (https://forums.factorio.com/20532)
— Fixed that assigning units to a unit group of a different force would corrupt the save. (https://forums.factorio.com/23699)
— Fixed crash when using can_insert on the quickbar from the Lua APi.
— Fixed tight spot scenario crash. (https://forums.factorio.com/23731)
— Fixed sort order for recipes in the recipe display.
— Fixed incorrect error message, when setting the number of filters on an inserter. (https://forums.factorio.com/23496)
— Fixed flame from rafineries that are marked for deconstruction was frozen in mid air. (https://forums.factorio.com/23733)
— Fixed that odd sized blueprints were shifted when rotated. (https://forums.factorio.com/24036)
— Fixed crash when clearing modded blueprint that doesn’t need item to be cleared. (https://forums.factorio.com/24035)
— Fixed crash in arithmetic combinator when calculating -2147483648/-1. (https://forums.factorio.com/23551)
— Fixed crash when assigning a character as a passenger of a vehicle when that character already is a passenger of another vehicle. (https://forums.factorio.com/24142)
— Fixed dealing damage could sometimes corrupt game state and saves. (https://forums.factorio.com/23965)
— Fixed modded save could not be loaded when a modded inserter gained abilities of smart inserter. (https://forums.factorio.com/23698)
— Fixed unknown-key message on the third level of first-steps. (https://forums.factorio.com/23362)
— Fixed cursor-split transfer (right click) not working when putting items into assembling machine stacks over normal stack size. (https://forums.factorio.com/23771)
— Fixed remote.call() from within the same mod. (https://forums.factorio.com/23587)
— Fixed inconsistent inserter behaviour when inserting into a splitter from the side. (https://forums.factorio.com/23669)
— Fixed train trying to turn around on a single rail. (https://forums.factorio.com/23371)
— Fixed internal electric network problems when mod specified irregular number as supply reach of power pole. (https://forums.factorio.com/23524)
— Fixed crash when lua script appears in specific state in multiplayer. (https://forums.factorio.com/23568)
— Fixed another crash than can happen when train destroys itself. (https://forums.factorio.com/23416)
— Fixed rare multiplayer crash «server is missing in the crcs». (https://forums.factorio.com/23376)
— Fixed several GUI problems on high DPI displays (https://forums.factorio.com/23593)
Optimisations:
— Improved performance when using landmines. (https://forums.factorio.com/23267)
Scripting:
— LuaUnitGroup::add_member now requires that the new member’s force be the same as the UnitGroup’s.
— Added LuaUnitGroup::force read-only attribute.

Changes:
— Mod checksums are calculated when the game starts and are compared with other peers when joining a multiplayer game. This is to ensure everyone has exactly the same mod in order to prevent desyncs caused by local changes made to mod files.
Bufixes:
— Fixed strange outer corner rendering for terrains with the same layer.
— Fixed Factorio timing out of a multiplayer game when closed by pressing the X button.
— Building things after quitting a multiplayer game is no longer possible and no longer crashes the game.
— Fixed memory leak with special signals in the circuit network.
— Fixed crash when killing the player in on_built_entity.
— Fixed crash when making blueprints of ghosts with some now-invalid circuit connections to other ghosts.
— Fixed player’s shooting target not updating properly when the target’s force became friendly
— Fixed the documentation of CircuitCondition
— Fixed that the ignore_planner field of Command would expect an integer instead of a boolean.
— Starting value of progress bar is now properly set based on the input.
— Fixed crash when destroying entity with empty corpse string.
— Fixed mining drills getting stuck when built pointing at rails and then rotated.
— Fixed remote.call() within the same mod passing invalid data.
— Fixed the typo in the error «mulitplayer.cannot-load-downloaded-map», the cause of the error wasn’t displayed because of it.
— Fixed that the server could get desynced and in a state where he has no one to download from.
— Fixed that the train tooltip was showing the current station as the next one when in the station.
— Fixed crash when a Lua function was used as a value in a table in data.raw.
— Fixed the tooltip of the inventory limit feature to «Limit the inventory part to be filled by machines.»,
so it is clear, it limits only input, but not output.
— Fixed that cancelling a recipe in the crafting queue would reset the crafting timer unnecessarily.
— Fixed crash when a force other than player, enemy or neutral was used in autoplace specification.
— Fixed crash when a network interface is deactivated during multiplayer game (https://forums.factorio.com/20078)
— Fixed white bar on top of the screen was sometimes present in fullscreen on OS X (https://forums.factorio.com/16720).
— Unified the processing of savegame name in —load-game —start-server and —mp-load-game. It can all be supplied with or without the .zip
— Fixed that collision with point wasn’t working properly for curved rail.
Modding:
— Added LuaEntity::unit_group read-only attribute
— Proper error message when subgroup specified by empty string.
— Fixed projectiles with negative acceleration would turn around, fly back and break the game.

Changes:
— Added —port to specify which network port the game should use, when hosting with —start-server or —mp-load-game.
This overrides the port specified in the config file.
Bugfixes:
— Explosion sounds are now not deafeningly load, when multiple things explode at once.
— Fixed LuaForce::clear_chart() would crash game if called while chart was refreshing.
— Fixed crash when refreshing chart while Direct3D device is lost.
— Fixed —config option not complaining about nonexistent file.
— Fixed crash when clicking on electric pole that was still in latency state.
— Fixed freeze of server with more than 255 different players in the savegame.
— Fixed crash when exiting the map editor while holding power armor on the cursor.
— Fixed map exchange string not using segmentation or water size correctly.
— Fixed Lua game_view_settings::showentityinfo read/write issues.
— Fixed fog-of-war does not work correctly in New Hope level 1.
— Fixed inconsistent Offshore Pump collision when building.
— Fixed desync reports were not generated.
— Fixed that non destructible entities get attacked, so biters could get stuck while trying to attack rails under train.
— Control settings window is now scrollable when it can’t fit the window.
— Fixed Factorio hanging on exit on Linux after copying or pasting