Hello,

When defining a NumberFieldEmbedding for a relative number field and then 
applying it to the field generator, I get a result which is different from 
the specified generator image:

sage: K.<sqrt2> = QuadraticField(2, embedding=1.414)
sage: L.<s> = K.extension(x^3 + (sqrt2/2 + 1/3)*x^2 + (2*sqrt2/5+3/7)*x - 1)
sage: my_embedding = NumberFieldEmbedding(L, QQbar, 
L.relative_polynomial().roots(QQbar)[0][0])
sage: my_embedding
Generic morphism:
  From: Number Field in s with defining polynomial x^3 + (1/2*sqrt2 + 
1/3)*x^2 + (2/5*sqrt2 + 3/7)*x - 1 over its base field
  To:   Algebraic Field
  Defn: s -> 0.5407496381556470?
sage: my_embedding.gen_image()
0.5407496381556470?
sage: my_embedding(L.gen())
0.01354690080260168?

Of course, I would have expected the last two results to be equal. My 
configuration: SageMath version 9.1, running on Ubuntu 18.04.3 LTS (64-bit).

This seems to stem from Sage somehow confusing the relative generator of L 
(over K) with the absolute generator of L (over QQ), even though I am not 
completely sure.

Should I open a trac ticket for this?

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