I installed a new vanity which comes with backsplash 4 inch high. Currently it has a 2 inch space gap below, between the mirror and the backsplash.
(a) What is a good product to fill in the space, so it does not damage the drywall behind? (trying to prevent water damage and mold etc).
(b) Or is the optimal solution to just move the mirror down 2 inches? If so, Is there a still a possibility water can leak between edges of mirror and backsplash?