Full notes
Full Fine Sweeper update
Read the full published notes in a cleaner layout. The original post stays linked below.
The January update (1.2.1.102) is finally here and despite my best effort, I've already got a report that it ate a player's save game. So if you have a great run in progress, and you want to finish it before updating, here's what you can do:
In your Steal library, right click on Fine Sweeper and select "Properties"
Switch to the "betas" tab.
Select the "legacy" branch. That's the old, DirectX9c version of the game
Restart Steam.
Once you've finished your game, please switch Fine Sweeper back to the "default" branch to receive the latest updates and enjoy the DirectX 11 version of the game. Sorry for the inconveniences.
Source
Changelog.gg summarizes and formats this update. How we read updates.