Prepare the lobster meat Drain any excess liquid from your cooked lobster meat. Pat it completely dry with a paper towel. Chop the meat into bite-sized chunks, roughly half an inch thick. Place the chunks into a large mixing bowl.
Mix the dressing In a small, separate bowl, whisk together the mayonnaise, fresh lemon juice, celery salt, and black pepper. Stir until the mixture is completely smooth.
Combine and chill Pour the dressing over the lobster chunks. Add the finely diced celery. Gently fold the mixture together with a rubber spatula. Stop mixing as soon as the meat is lightly coated. Place the bowl in the fridge for 10 minutes to let the flavors blend.
Toast the buns Heat a large skillet over medium-low heat. Brush the flat, outer sides of the split-top buns with the melted butter. Place the buns in the warm skillet. Toast them for 1 to 2 minutes on each side until they turn golden brown and slightly crispy.
Assemble and garnish Open the warm, toasted buns gently. Spoon the chilled filling generously into each bun. Sprinkle the top of each roll with fresh chopped chives. Serve immediately.