Abstract: Window film (e.g., solar film) is edge-sealed by moving a porous applicator tip saturated with liquid sealant in wiping contact along an edge of the window film to be sealed so as to transfer a portion of the liquid sealant from the saturated applicator tip to the window film edge. Thereafter, the liquid sealant is allowed to dry so that a residue of the sealant (e.g., most preferably a solvated plastics material) remains as a transparent layer sealing the space between the window film edge and the adjacent window glass frame. Most preferably, a kit is provided which includes a pen-like applicator and a container which contains a quantity of liquid sealant. The applicator is provided with the porous applicator tip at one end in fluid communication with a barrel defining an interior reservoir space.