Halfglass Trio

L-shaped packets lay three matching triangle halves at once. Overlap only complementary halves and complete every square of three glass panes. Aim the top-left anchor, rotate the three-cell L footprint and Fit. The triangle orientation is fixed by the six-packet forecast: R, L, R, L, R, R. A packet can add R to an L cell, but never R to R. Sealed rows cannot be touched again. All twelve squares need both halves to finish. Undo restores the previous packet and sealed rows. No timer.