On my Nexus 5, since Android updated to marshmallow, the Wi-Fi is draining the battery way too fast, even when disabled. See the screenshot:
(Click image to enlarge)
I've seen this question: Battery drain when wifi is off but since I've a very stable network, the answer doesn't fit my need.
I've disabled the Location, I doubt that the issue could come from here.
Where should I look next?
The real question is in fact "How come that the WiFi usage bar is going from 100% until now even if Wi-Fi is Off?"