When you have Smoke Traps perk unlocked you can infinte stack the buff: Dusk Shroud which can provide you crazy amount of Dodge rate and Glancing blow chance.
I don’t know if it’s intended but I don’t think so since it will be too broken when you can have like 80%+ dodge chance and 100% Glancing Blow chance forever without any gear investment
This is not a bug. This is exactly how the buff works, because you cannot stack it “infinitely”: every stack has its own duration. They do not prolong themselves indefinitely.