Preheat your oven to 375°F (190°C).
In a large mixing bowl, combine the thawed spinach, chopped artichoke hearts, minced garlic, grated parmesan cheese, softened cream cheese, and half of the shredded mozzarella cheese. Season with garlic salt and black pepper to taste. Mix until well combined.
Open the can of seamless crescent dough and unroll it on a lightly floured surface. Gently press the seams together to create a single sheet of dough.
Using a sharp knife or pizza cutter, cut the dough into squares or circles, depending on your desired shape and the size of your bites.
Place a spoonful of the spinach dip filling in the center of each dough piece. Be careful not to overfill.
Fold the corners of the dough over the filling to create a pocket. Pinch the edges to seal tightly.
Place the filled bites on a baking sheet lined with parchment paper. Sprinkle the remaining mozzarella cheese on top of each bite. Bake in the preheated oven for 15-20 minutes, or until golden brown.
Once baked, remove the Spinach Dip Bites from the oven and let them cool for a few minutes. Serve warm with your favorite dipping sauce or enjoy them on their own!