The thinning dynamics of a liquid neck before break-up, as may happen when a drop detaches from a faucet or a capillary, follows different rules and dynamic scaling laws depending on the importance of inertia, viscous stresses, or capillary forces. If now the thinning neck reaches dimensions comparable to the thermally excited interfacial fluctuations, as for nano-jet break-up or the fragmentation of thermally annealed nanowires, these fluctuations should play a dominant role according to recent theory and observations. Using near-critical interfaces, we here fully characterize the universal dynamics of this thermal fluctuation-dominated regime and demonstrate that the crossover from the classical two-fluid pinch-off scenario of a liquid thread to the fluctuation-dominated regime occurs at a well defined neck radius proportional to the thermal length scale. Investigating satellite drop formation, we also show that at the level of the crossover between these two regimes it is more probable to produce monodisperse droplets since fluctuation-dominated pinch-off may allow the unique situation where satellite drop formation can be inhibited. Nonetheless the interplay between the evolution of the neck profiles from the classical to the fluctuation-dominated regime and the satellites production remains to be clarified.< Leer menos