Can you share some screenshots next time this shows up? One of my friends said he didn't get this notification while using his Nano X with Electrum 3.3.8, and it's my first time hearing about this too. Does this mean Nano X judge that a beta version is the latest version that the user should use then?
I am quite sure I got the same message on Electrum 3.3.8 a few days earlier. It is related to
this vulnerability which has been fixed in the Ledger Live and Bitcoin app update. Third-party software needs to be updated as well (see
#6230). Your friend might have not updated his device.
Here are the photos you asked for.
By the way,
a new beta version has been released.