In a mixing bowl, stir together the Jamaican jerk seasoning, soy sauce, olive oil, and minced garlic until a thick paste forms.
Place the chicken thighs in the slow cooker and pour the seasoning paste over them. Turn the thighs to coat evenly, then sprinkle with salt and black pepper.
Cover the slow cooker and cook on low for 6 to 7 hours until the chicken reaches an internal temperature of 165°F and pulls away from the bone easily.
About 15 minutes before serving, combine the diced pineapple, red onion, cilantro, and lime juice in a bowl to make the salsa. Taste and add a pinch of salt if needed.
Remove the chicken thighs from the slow cooker and serve them topped with generous spoonfuls of the pineapple salsa.