I'm running Ubuntu 18.04 on a Dell Precision 5520 laptop with a Microsoft wireless keyboard 3050 and wireless mouse 5000. Before upgrading from Ubuntu 16.04, I could power down at the end of the day and come back the next day to find a fully charged battery. After upgrading, I would power down at the end of the day and find that my battery was below 90% when I returned to work the next day. Last night, I unplugged the USB wireless receiver after I powered down the laptop. This morning, the laptop's battery was fully charged when I turned on the computer. So, it seems that the wireless receiver continues to draw power even after the computer is off.
This issue may also be related to the erratic behavior of the mouse cursor on startup. When I leave the wireless receiver plugged in over night, the mouse has significant skipping and lag behaviors on startup the next day.
Why is the wireless receiver drawing power in 18.04, when it didn't in 16.04? And what can I do to prevent that behavior, other than unplugging the receiver every time I power down the laptop?