Feature request: scrolling the table of contents sidebar simultaneously


In the view mode, I have to scroll the table of contents sidebar on the right side manually when it gets longer.
I want the scroll position of TOC sidebar to sync with current viewport.
The attached image shows the TOC sidebar not showing current section—Typography section.
Tested on Google Chrome, Ubuntu 16.04.2

No files, tests, or entry points are named. Start by locating the view-mode table-of-contents sidebar and the viewport scroll handling, then determine how the current section is identified. Done means the sidebar scroll position stays synchronized with the current viewport so the active section remains visible.

Scritto dal modello di indicizzazione a partire dal testo della issue.