https://www.reddit.com/r/SteamDeck/comments/tyuu84/comment/i3vfve2/
According to this comment, it is okay to "grab a Lenovo uefi update pack" and extract the .exe uefi flasher from it, then use the said .exe flasher to flash firmware for the steam deck.
Any problems if doing something like this?
Sometimes, at your own risk.
Most hardware manufacturers don't build their own UEFIs, but license them from companies specialized in creating UEFIs and customize them for a particular product. Different hardware based on the same UEFI platform will likely share the flashing software.
In this particular case it seems that both Steam Deck and some Lenovo hardware are based on Insyde H2O UEFI.
By following this procedure you're taking the responsibility for any problems. They won't be covered by the warranty.
UEFIs themselves aren't interchangeable, with very rare exceptions, and even then patches will be required.
