From Kerbal Space Program Wiki
Version 1.12.3 is a bugfix update that was released on December 13th, 2021. This bugfix focused on "drift" that occurred with docking ports and Breaking Ground robotic parts. This was the last bug fix before KSP 2.
- Fix AOORE in Assembly Loading of Duplicate Mod DLLs causing issues with loading of some mods.
- Improved robotic parts drift when robotic parts are left locked. Players can now quicksave/reload or timewarp to reset part placement. Note: The drift issue can only be corrected when the robotic parts are set to locked mode.
- Improved rotating docking ports drift when rotating docking ports are left locked. Players can now quicksave/reload or timewarp to reset part placement. Note: The drift issue can only be corrected when the rotating docking ports are set to locked mode.
- Add UpgradePipeline support for PartModule renaming.