Via [url=https://blog.counter-strike.net/index.php/2022/03/37380/]the CS:GO blog[/url]:

[quote=Valve][MAPS]
Ember:
– Dramatically increased FPS by roughly 30-50% in most areas
– Changed spawn selection and loading screen image designs
– Revamped spawn selection location names
– Fixed radar alignment for spectators
– Elevator no longer kills you when stood underneath the doors
– Items can now appear behind the Lighthouse and at the underground geyser
– Added new rock path in Ruins (previously named Kasbah)
– Fixed stuck spot in Ruins
– Added new jump path to roofs at Industry (previously named Town)
– Fixed misaligned clips at Industry
– Lowered wall height to create a new route at Research (previously named Charlie)
– Improved movement on stairs at Rock Pool B (previously named East Tunnel)
– Remade collision mesh on all rock props to increase accuracy
– Added new “chumble” models to further dunglify the chunky flumpston areas
– Improved lighting at various parts of the map
– Optimized water material
– Fixed some areas where it was possible to see through walls
– Other minor fixes (Thanks Joaokaka1998)

Vineyard:
-Fixed stuck spots
-Fixed various bugs[/quote]

Rumor has it:

- Additionally, there's a few Steam Input improvements (Steam Deck is out, after all) and some scattered localization file updates: https://github.com/SteamDatabase/GameTracking-CSGO/commit/557cb1b37739a00bb05e811ced43ed971e8d1434

- Size is close to 300 MB