  It was recently demonstrated that two-dimensional Townes solitons (TSs) in
two-component systems with cubic self-focusing, which are normally made
unstable by the critical collapse, can be stabilized by linear spin-orbit
coupling (SOC), in Bose-Einstein condensates and optics alike. We demonstrate
that one-dimensional TSs, realized as optical spatial solitons in a planar
dual-core waveguide with dominant quintic self-focusing, may be stabilized by
SOC-like terms emulated by obliquity of the coupling between cores of the
waveguide. Thus, SOC offers a universal mechanism for the stabilization of the
TSs. A combination of systematic numerical considerations and analytical
approximations identifies a vast stability area for skew-symmetric solitons in
the system's main (semi-infinite) and annex (finite) bandgaps. Tilted
("moving") solitons are unstable, spontaneously evolving into robust breathers.
For broad solitons, diffraction, represented by second derivatives in the
system, may be neglected, leading to a simplified model with a finite bandgap.
It is populated by skew-antisymmetric gap solitons, which are nearly stable
close to the gap's bottom.
