“…Recently, great attention has been devoted to the study of a new class of fractional Sobolev spaces and related nonlocal problems, in particular, in the fractional Orlicz-Sobolev spaces W s L Φ (Ω) (see [6,7,13,14,17,19,24,25]) and in the fractional Sobolev spaces with variable exponents W s,p(x,y) (Ω) (see [8,9,10,11,12,15,16,33]), in which the authors establish some basic properties of these modular spaces and the associated nonlocal operators, they also obtained certain existence results for nonlocal problems involving this type of integro-differential operators. Furthermore, in that context, the authors in [5] introduced a new functional framework which can be seen as a natural generalization of the above mentioned functional spaces.…”