Crossword puzzle clue "glass squares"

The squares of "three squares"

Glass squares

Like the glass, when viewed by someone who's pessimistic about how much liquid is in the glass

Small glass disk used as an ornament in a stained-glass window

Novella whose final words are found in the circled squares

Annual solving competition held in Brooklyn, briefly ... and a hint to nine squares in this grid

Country squares?

Popular browser extension ... or a literal description of four black squares in this puzzle