The Driver: the share button at the top right of the Big Picture dashboard is too large. Measured: the
research-dashboard topbar is 38px tall, but ShareButton is the map toolbar's 40px round button (36px under
768px) plus a 2px rainbow ring, so 44px, taller than the bar it sits in, and clipped top and bottom.
In this bar only (.rd-topbar), the button is 28px and its icon 15px: with the ring it is 32px, the height of the
bar's own search box, centred with 5px above and below. Measured after, at 1440 and 390, on the Big Picture
(dashboard-plus-grid) and research-dashboard leaves: the bar stays 38px; the title, search box and Align button
keep their sizes. Map toolbars keep their 40px share button. Rebuilt research-dashboard + dashboard-plus-grid,
tree regenerated.