Rollback your Steam OS Version to the Previous Version if you aren't happy with a recent Steam OS version you can follow this simple guide to revert to a previous version effectively downgrading Steam OS.
Here is what you need to do to rollback your version:
Go to the power menu and shut down your steam deck
Wait for it to completely shut down and give it a few seconds so that the logo disappears
Hold down the power button and the three dot menu at the same time but only until you hear the boot sound then keep the three dot menu pressed but let go of the power button
If you've done it correctly you will see a new menu
For me the current EFI is the current steam OS update, at the time of this article that was the 342 which was updated on the day of this article.
The previous version which was three days prior was another Steam OS version now this should be 333 for me so if I just select that.
You will see a sudden flood of commands and the Steam Deck will reboot and be on the previous update.
There is one catch, if you restart your Steam Deck it will revert to the current version unless you put your Steam Deck in offline mode before you reboot.