The additional fingering digit in FE can be explained with Chopin proofreading of this edition, which is supported by numerous additions of these types over the entire Etude. In the case of EE2 (→EE3), an authentic proofreading is out of the question (cf. the Etude in F minor, No. 2), hence one should assume that the reviser of EE2 used a copy of FE while performing additions. Apart from the digit in bar 4, fingering was added in bars 8-10, 11, 14-15, 17-26. It is noticeable that EE2 repeats the majority of, yet not all fingering digits included in FE. In some situations, one can explain it with an oversight, e.g., at the transition between bars 14-15, yet omission of additions in bars 37-41 could have been intentional.
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category imprint: Differences between sources
issues: EE revisions, Authentic corrections of FE
notation: Fingering