Scrolling happens in two jumps.
Replace litera's plugin with this one: https://github.com/Arwid/jQuery.scrollIntoView. This seems to allow multiple targets.
Tried using Arwid's plugin. It doesn't support the :scrollable selector. This broke a lot of other code. 663943300fc689ab07d37cf1de5bc9e7cf35a864
Made some adjustments to litera's plugin. 7154eb22fcb8b7e44da438e37ffadc441a351c42 on f/plugin3 Seems to cover some basic cases, but not reliably tested yet.
Naive union is not completely desirable: if target doesn't fit in the viewport, we must make sure the anno is visible!
(A priority list perhaps?)
Worth investigating: (1309 stars) https://github.com/flesler/jquery.scrollTo
Doesn't have :scrollable selector ... would need both.