Q. Is it proper to light the menorah next to a window covered with frosted glass, that shows there is light but one can’t tell if it is a menorah or how many candles are on?
A. Kovetz Halochos (Hilchos Chanuka 9: 10: p. 152) rules that if you can see from the outside that there is light, it is permitted lekatchila (on the onset), to light the menorah next to that window.
Horav Shlomo Miller’ Shlit’a opinion is similar.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a