Popular v0.9.1

Fixed

• The docs sidebar scrolls when it outgrows the window. On a long page the
  current entry nests every heading beneath it, which makes the sticky sidebar
  taller than the viewport, and a sticky element taller than the viewport
  cannot be scrolled: the entries below the fold, including the links to the
  other docs pages, were unreachable until you had scrolled through the whole
  article. The sidebar now stops at the bottom of the window and scrolls on its
  own, and the scroll-spy keeps the highlighted entry in view as you read.