In the event anyone is using Mod "Mining Drones 2.0 Remastered" by AivanF, In startup of this mod is option to either have productivity research for drones and regular mining either separate or combined.
And if chosen combined, this mod for some weird reason than replace entire mining productivity research. Which in practice means there is no mining productivity bonus to your drones. Which kind of defeats the purpose of having them combined in the first place.
