I was wondering if anyone had any brightness/sleep issues with their MacBook Pro after installing macOS High Sierra. Right after installation, the first thing I noticed is how I can no longer control the brightness, similar to some of the side effects some unsupported Macs were experiencing at https://forums.macrumors.com/threads/macos-high-sierra-10-13-unsupported-macs-thread.2048478/ . Also, whenever my Mac goes to sleep, it never wakes up. You can try to wake it. The keyboard backlight will turn on, but the screen won't. The Sleep Indicator Light will remain on even during sleep (it no longer pulsates slowly) or after you've pressed a couple keys and the keyboard backlight turns on. I've tried resetting the SMC (every step BUT the one requiring you to sleep/wake your mac), resetting NVRAM, booting in Safe Mode and logging in as another user. Nothing has worked yet, but I'm sure I'm not the only one experiencing this.