As a result of comparison of the indications of FE in bar 646 and 648-650, we interpret the mark in this bar as a long accent, referring to both hands. The absence of the mark in GE is most probably an oversight of the engraver.
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category imprint: Differences between sources; Editorial revisions
issues: Long accents, Placement of markings, Errors in GE
notation: Articulation, Accents, Hairpins