Bootstrap 3 Fixed Top Navbar 'Flickering' On Mobile Scrolling using jQuery One-Page Scrolling Effect

Try this

{
  -webkit-backface-visibility: hidden;
}

Reference: https://developer.apple.com/library/content/documentation/InternetWeb/Conceptual/SafariVisualEffectsProgGuide/Using2Dand3DTransforms/Using2Dand3DTransforms.html#//apple_ref/doc/uid/TP40008032-CH15-SW40

I had also 1px jumping problem with bootstrap navbar.

Solved by adding this to parent element (in my case <header>)

  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  position: fixed;
  z-index: 1000;