Affix is not working in Bootstrap 4 (alpha)

Question

According to Bootstrap 3 docs I have added following attributes to a navbar:

Answer 1

As per Vucko's quote within the Mirgation docs, ScrollPos-Styler library suited me quite well.

1. Include the .js ScrollPos-Styler (scrollPosStyler.js) file to your page.
2. Find the relevant
   you wish to make 'sticky'

3. Apply sps sps--abv class

4. Add .css styles you wish to have triggered once the element has become sticky (As per the demo page.

---

/** 
 * 'Shared Styles' 
**/
.sps {

}

/** 
 * 'Sticky Above' 
 *
 * Styles you wish to apply
 * Once stick has not yet been applied
**/
.sps--abv {
   padding: 10px
}

/** 
 * 'Sticky Below' 
 *
 * Styles you wish to apply
*  Once stick has been applied
**/
.sps--blw {
   padding: 2px
}