We interpret the quite ambiguous mark written in FED at the end of bar 18 as a slur. The necessity to combine the last quaver in bar 18 with the following minim is clearly indicated by the Chopinesque fingering and probably also by the mark written in FEH.
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category imprint: Graphic ambiguousness; Differences between sources
issues: Annotations in teaching copies, Annotations in FED, Annotations in FEH
notation: Slurs