I went to sleep last night at 00:00 with my phone having 24% charge left. When I woke up at 5:00 this morning, the phone had died. I plugged it in, checked battery saver and found out the Windows Default Lockscreen app had used 40% charge in the past 24 hours. It's weird because when I checked yesterday's afternoon, it didn't show up on the list. On the contrary, Edge has been behaving so nicely on my phone, with only 1.2% charge used. I don't even know what that is. Here is a picture that I have just taken