We introduce and study new categories Tfrakturg,frakturk of integrable g=sl(∞)‐modules which depend on the choice of a certain reductive in frakturg subalgebra k⊂g. The simple objects of Tfrakturg,frakturk are tensor modules as in the previously studied category Tg [Dan‐Cohen, Penkov and Serganova, Adv. Math. 289 (2016) 250–278]; however, the choice of frakturk provides for more flexibility of nonsimple modules in Tfrakturg,frakturk compared to Tg. We then choose frakturk to have two infinite‐dimensional diagonal blocks, and show that a certain injective object Kmfalse|n in Tfrakturg,frakturk realizes a categorical sl(∞)‐action on the category Omfalse|nZ, the integral category scriptO of the Lie superalgebra gl(m|n). We show that the socle of Kmfalse|n is generated by the projective modules in Omfalse|nZ, and compute the socle filtration of Kmfalse|n explicitly. We conjecture that the socle filtration of Kmfalse|n reflects a ‘degree of atypicality filtration’ on the category Omfalse|nZ. We also conjecture that a natural tensor filtration on Kmfalse|n arises via the Duflo–Serganova functor sending the category Omfalse|nZ to Om−1false|n−1Z. We prove a weaker version of this latter conjecture for the direct summand of Kmfalse|n corresponding to finite‐dimensional gl(m|n)‐modules.