Aight bruv. Safe.
(I nearly exposed a terrible secret. Phew.)
What's blue text?
(DYSWIDT?)
She doesn't really have one. Because she is the fucking Queen. And nobles were [Forename] of [Place].
But they made it 'Windsor' sometime in the 20th C.
Windsor, but the 'family name' has changed over the centuries as they're a bunch of in-bred/out-bred whores'n'villians.
Before Windsor, I think it may have been Saxe-Coburg, which was a bit too germanic for the early part of the last century.
Battenberg, Mountbatten and Mountbatten-Windsor are all in there somewhere too.
These Royals know how to make it complicated.