scrolltrack.js
This tracks a users scroll location on the y axis and returns the user to that location on refresh by storing the data in a cookie. With the first parameter, you can apply a frequency for the function to check the scroll position (in second; the default is 2). The second parameter indicates the duration of the cookie (in days) where the scroll position is stored.
Load jquery, then js-cookie, then this script, and execute $.positionTrack(), and that's all.
ex:
$.positionTrack()
$.positionTrack(1)
$.positionTrack(1, 365*3)
Requires jscookie https://github.com/js-cookie/js-cookie