P: White dot in bottom left corner

Whenever I open adobe Lightroom for Mac there is a small white dot in the lower left corner of my Mac display. I freaked out the first time because even when I minimized the app it was still there. Thought I had a bad pixel or something. Terminating the app makes the dot go away. I even youtube'd recent videos of people using Lightroom and that same white dot is there. Anyone know what this is? Im assuming its a simple bug and am wondering if both Mac and windows users are experiencing the same thing. Appreciate any feedback. Thanks!