no built-in reflexivity of list embedding (which is more standard; now embedding is reflexive whenever the base-order is)
no built-in reflexivity of list embedding (which is more standard; now embedding is reflexive whenever the base-order is)

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle