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A catastrophic collapse of wavepacket is considered for the propagation of surface waves in the finite depth fluid eventually resulting in foam
formation. That propagation is described by non-integrable Davey-Stewartson equation (DSE) which is a nonlocal version of 2D
nonlinear Schrodinger equation (NLSE). Another application is the laser beam propagation in the nonlinear optical media
with both Kerr and quadratic nonlinearities. An excess of a wave action integral above a critical level results in finite time singularity
(collapse) of DSE solution. It is found that DSE collapse obeys the tail minimization principle when physical systems dynamically choose
self-similar-type solution which minimizes the spatial tails of the collapsing solution on the border of the spatial collapsing region. This
minimization ensures that the singularity (collapse) is reached in fastest possible time because with the critical wave action captured in the
collapsing region. That critical wave action is determined by a universal anisotropic self-similar collapsing profile. A weak escape of wave action
from that region is controlled by an analog of quantum tunnelling resulting in log-log modification of collapse scaling which resembles a
collapse in 2D NLSE.