The absence of the slur in A is probably Chopin's oversight. The bar is the first one on a new page, and the notation reveals distraction, probably following from haste – there is also no staccato dot under G in this bar and treble clef in the next one. Due to this reason, in the main text we give this slur, although the authenticity of the addition introduced in GE1 remains uncertain.
Compare the passage in the sources »
category imprint: Differences between sources
issues: Authentic corrections of GE
notation: Slurs