The short answer? It doesn't hurt: "Toners, by and large, have some astringent properties, so they remove excess traces of oil, make-up, sweat and dirt from the surface of the skin," says board-certified dermatologist Ava Shamban M.D., founder of SKINFIVE.
And while these properties likely work better when applied directly to the skin, the mask hack might be worth trying out if a pinch. "You can certainly spray a toner on the inside of a mask," continues Shamban. "Its antibacterial quotient, anti-inflammatory agents, soothing and oil-absorbing properties can be an additional aid in the fight against maskne."
Sounds pretty promising considering that all it takes is a few spritzes into face covering. Of course, there aren't any clinical trials to support this hack yet – just the anecdotal claims of those affected by masks online – but the ingredients behind it make sense.