Adjust oven rack to middle position and preheat to 350 degrees F. Grease sides of 13- by 9- by 2-inch pan. Stir crushed chocolate wafers with butter, sugar, and salt until moistened. Firmly press into bottom of prepared pan. Scatter milk chocolate chips into pan. Layer coconut, almonds, and then bittersweet chips on top. Evenly drizzle condensed milk on top. Bake until golden and bubbling, about 30 minutes. Transfer pan to wire rack to cool completely before cutting into squares.
