Glowing/smoking missions


helo friends!
i googled, cheсked faq and didnt found any answer.
what means this fog/smoke on missions on a map? does it have sense? i passed html and it wasnt smoking at all… i passed gamedev and it was smoking and after i passed it still do… what its all about. please give an answer


missions with blue smoke = not yet unlocked subscriber levels
yellow smoke = challenge
red smoke = i forgot


thank you for response.
now i see in the forest that blue smoke means locked missions.
so i can say that gamedev is a buggy location. there was a blue smoke but missions were available and i passed all the missions and they still with blue smoke)))