Found a solution. Restore the image search-icon.png in /wp-content/themes/vantage/images/sprites/). If you need to download images, grab it from here.
Next in the css file (In wordpress go to apperance>editor>vantage: Stylesheet(style.css).
Locate this line:
#search-icon #search-icon-icon,#search-icon #search-icon-icon .icon-search{
-webkit-transition:all 0.4s ease;
-moz-transition:all 0.4s ease;
-o-transition:all 0.4s ease;
transition:all 0.4s ease;
}
And change to this:
#search-icon #search-icon-icon,#search-icon #search-icon-icon .icon-search{
-webkit-transition:all 0.4s ease;
-moz-transition:all 0.4s ease;
-o-transition:all 0.4s ease;
transition:all 0.4s ease;
/*custom added to fix missing icon*/
background: url('images/sprites/search-icon.png') no-repeat;
background-size:20px 20px;
background-position-y: 19px;
background-position-x: 19px;
}
For proof that this works, checkout https://www2.dataconnectivity.co.uk.
I’m still uncertain to why icons were deleted etc, but it’s a working solution.
Also, restore the image “sprites-1-2.png” found in /wp-content/themes/vantage/images/, which has images including the scroll-back-to-top icon.