All paths in AI get selected when you draw a marque over their edge (with no points inside selection). Segment got selected. It is fine.

But mesh objects are immune to edge marqueing, because there is no 'segment' thing for a mesh. WHY? Why don't you make the same thing as it's done for paths? Just select seam between mesh points and allow to move both points adjacent when seam is 'selected'.

I put this into Bugs, because I consider this a bug rather than request. Like 'Selecting segments in mesh is broken all these years since introduction and everybody just silent about it'.

P.S. Thank you for quietly fixing unenlargeable markers for mesh objects, I appreciate it a lot