  We establish an infinitesimal version of fragility for squared Dehn twists
around even dimensional Lagrangian spheres. The precise formulation involves
twisting the Fukaya category by a closed two-form or bulk deforming it by a
half-dimensional cycle. As our main application, we compute the twisted and
bulk deformed symplectic cohomology of the subflexible Weinstein manifolds
constructed in \cite{murphysiegel}.
