Reviewer B: The article is fine. No major suggested modification, except for the 2 following ones:
Since the minimum mass for deuterium fusion is \(13\) times the mass of Jupiter, this criterion has been adopted to determine the maximum mass of an extrasolar planet, just as brown dwarfs are defined by the minimum mass of hydrogen burning. Brown dwarfs can therefore have masses similar to those of planets. This is the reason why some young low-mass brown dwarfs are called free-floating planets or planemos (planetary mass objects).
This part should be dropped, as it only brings confusion. Even though the minimum mass for D-fusion was indeed adopted by the IAU to distinguish planets from brown dwarfs, this definition is of purely semantic nature and thus does fit into the presently scientifically-motivated article. As written in the previous sentence by the author herself, brown dwarfs can form down to a few (5 or so) Jupiter masses, showing that D-fusion plays no particular role in BD formation. The various, confusing terminologies "free-floating planets" and "planemos" should be dropped.
2) Caption of Fig. 1 Non-experts in the field do not know what the "NextGen" models refer to. Moreover, it is my understanding that the mass-radius relationship, i.e. the mechanical properties of an object, depend only weakly on the atmosphere (in contrast to the thermal properties). The caption should thus refer to the proper reference (eg the Chabrier & Baraffe ARAA).