Macbook Pro, 2017 (touchbar), OSX Sierra, Premiere Pro 2018 12.0.1 I spent many days troubleshooting this persistent bug myself across several versions of Premiere Pro: with and without a second monitor attached, holding shift, etc.
Pro CC lets you edit video faster than ever before. Dozens of brand-new features include a timeline, improved media management, and streamlined color grading. And it's just the beginning: You'll get access to new features the moment they're released. Your entire creative world, together in one place. Only in Creative Cloud. Edit more naturally using touch and gestures: Perform a wider range of editing tasks using your Surface Pro, tablet or Apple trackpad.
Scrub clips, mark I/O, drag and drop clips to the Timeline and more. Deliver high-quality HDR video: Keep up with the demands of evolving color workflows. Premiere Pro introduces initial support for high dynamic range (HDR) technology, so you can work with video that shows rich detail even in the highlights and shadows. New HDR scopes and Lumetri controls let you make precise adjustments.