EN
Let G be a locally compact group with a fixed left Haar measure. Given Young functions φ and ψ, we consider the Orlicz spaces $L^{φ}(G)$ and $L^{ψ}(G)$ on a non-unimodular group G, and, among other things, we prove that under mild conditions on φ and ψ, the set {$(f,g) ∈ L^{φ}(G) × L^{ψ}(G): f*g$ is well defined on G} is σ-c-lower porous in $L^{φ}(G) × L^{ψ}(G)$. This answers a question raised by Głąb and Strobin in 2010 in a more general setting of Orlicz spaces. We also prove a similar result for non-compact locally compact groups.