So after replacing the battery in my One (M8) with a new one from eBay, the notification light just blinks orange when charging. When swapping back to the battery before replacement, it, at least, shows a battery charging screen. What am I doing wrong? I've heard something about 'deep discharge' where it needs to be on the flashing light for 15 to 30 minutes to actually start charging or something like that.
Is this new battery a dud? Should I keep charging it? Really don't know what to do at this point...
Update! I reseating the battery connector on the motherboard and now it's a solid red light when plugged in! Hooray! When pressing the power button, though, nothing is shown on the screen. It's still all black. I just now replaced the screen, since I broke the LCD below the glass last time I tried to take it apart.