With Lightroom 2015.7 on macOS Sierra (released today) the scrolling behaviour for changing brush sizes using the trackpad is very "twitchy". It will jump from tiny to large with very small scroll movements. All other scrolling in the OS as well as the rest of Lightroom is unaffected and works as normal.
Areas of issue:
- Adjusting size of spot removal tool - Adjusting size of the adjustment brush
Unaffected: - Scrolling the grid view - Panning around the image with 2 fingers
I've tried with the GPU on and off.
15" 2014 MacBook Pro with 16G ram and SSD (65% full). 2.2Ghz i7.
Actual behaviour: The best I can do is describe it as twitchy. In the previous version using the scroll action (two fingers on the trackpad moving up and down) the brush sizes would adjust in a smooth and linear manner. The current behaviour has the size jumping (smoothly, no going from big to small with nothing in the middle) very fast from big to small or back. I can make more delicate size changes by moving my fingers *very* slowly on the trackpad.
This feels very much like like someone has changed my mouse sensitivity to max, except it hasn't changed (default sensitivity in the accessibility trackpad options) and in the rest of the system the scrolling "feel" feels exactly the same as in the previous OS version.