In a large pan, saute onion, green onion, and garlic together over medium heat until soft and translucent. Add spinach and parsley, continue to cook until wilted down to almost nothing. Drain well, cool to room temperature.
Squeeze out any remaining liquid, transfer to a mixing bowl.
Add dill, feta, and eggs, stir until everything is well incorporated. Season with salt and pepper, to taste.
Preheat oven to 375, line 2 baking sheets with parchment paper.
Unroll one tube of phyllo sheets carefully. Lay one sheet out on your work surface. Lightly but completely brush with melted butter, lay another sheet on top, and brush with butter. Cover the remaining sheets of phyllo with a lightly damp towel to keep them from drying out.
Cut the sheet pile lengthwise into 4 long strips.
Place a heaping tablespoon of spinach filling at one end of each strip. Fold one of the end corners over the filling, meeting the short end up with the long side of the strip. (IE: That end of the strip will now have one point, with a covered triangle shaped "dumpling".)
Fold the triangle "dumpling" up along the length of the strip, "flag style", until reaching the end. Tuck under any remaining overhang of phyllo sheet, place on prepared baking sheet.
Continue with remaining dough and filling, until you run out of one, the other, or both.
Lightly brush the tops of each spanakopita with melted butter, bake for 17-20 minutes. Pastries should be golden brown.
Serve warm, preferably with some tzatziki to dip them in!