Hi All! I installed Ubuntu Mate 18.04 on a Dell Latitude E5470 (i5-6300u), and I'm having trouble with it not sleeping. The screen turns off, but the power LEDs are still on, the keyboard backlight stays on until its normal timeout, and it drains the battery a lot faster than it should for being asleep. On top of that, it only "wakes" up to the power button, but not the keyboard or touchpad.
This is a bone-stock install--all I've done since installation is an apt-get update && apt-get upgrade.
I have no idea where to look to start figuring this out. Where do I go to start debugging this? Is there some sort of missing driver I need to install?