Context: 1. Adjust the water temperature to achieve a desired dough temperature of 73-76°F. Place the bread flour, water 1, yeast and salt in the mixing bowl. 2. Add the liquid levain. 3. Add the spelt poolish. 4. Add the whole wheat sponge. 5. Mix on first speed for 5 minutes, occasionally scraping the mixing bowl. 6.: Mix on second speed for 3 to 4 minutes, until the dough reaches a strong improved mix. 7. Add water 2 in 3 stages on second speed.Make sure all the water is incorporated after each addition. After mixing, dough appears very wet and soft but still maintains the strength. It should form a well developed window. Place 5 kg of dough per oiled dough bin. Bulk ferment the dough at 78°F for 2 hours with a fold every 45 minutes, 2 folds total. Question: Here is another question with the same context of another post. I am totally confused about the term "a well developed window", the "window" seems making little sense here. Thank you.