Sprinkle cucumber slices with salt in a large bowl and allow them to sit for 1 hour to release moisture.

Drain the liquid from the cucumbers but do not rinse them. Add the sliced onions to the cucumbers.

In a small saucepan, combine white vinegar, water, and sugar over high heat. Stir constantly until the sugar dissolves completely and the liquid becomes clear, which should take about 3 to 5 minutes.

Pour the vinegar mixture over the cucumbers and onions. Add the minced dill and mix well. Cover the bowl with plastic wrap and refrigerate for 1 hour. Serve chilled or at room temperature.