It is difficult to say whether the 
indication was omitted by FE (→GE,EE) due to a proofreading intervention, probably performed by Chopin, or whether we are dealing with an oversight by the engraver. Nevertheless, we acknowledge this change as probably having been accepted by the composer, who introduced a number of changes to this and the adjacent bars while proofreading FE1, including added performance markings – see notes to b. 95-99 and 99 and 103-105 as well.
Compare the passage in the sources »
category imprint: Differences between sources
issues: Errors in FE, Authentic corrections of FE
notation: Verbal indications