focusRingThickness

The dotted keyboard-focus ring's stroke, and the one number here that is not a phone pixel.

Windows Phone had no keyboard navigation and therefore no focus visual to copy; Windows 8 did (drawKvadrantFocusRing), and its Rectangle takes Shape.StrokeThickness's default of 1. A WinRT unit is 1/96 inch against dp's 1/160, so research §1.6c converts it at ×1.667 rather than the ×0.75 every other line of this class is scaled by — the two lineages measure in different things, and running this one through the phone's factor would be arithmetic on a unit it was never in.

The dash pattern and the gap are read off the same thickness, so this is the ring's only number. See drawKvadrantFocusRing.