there are a few of these libraries but as far as i can tell they are just hacks that only work with a background image, and are thus not a drop in replacement for backdrop-filter. a replacement for blur maybe.
All of the libraries I have seen seem to just be jquery libraries that apply a blur CSS effect to DOM elements. This is NOT supported very well accross different browsers.
Frosted Panel is a cross browser solution which allows you to have a full scale, centered, background-image with a responsive, blurry panel overlapping it, of which you can put whatever content you would like inside.
It works by taking advantage of SVG filters, which are supported in most (if not all) browsers, while panning and zooming a duplicate SVG image of the original background-image in order to mimic the actual background-image of the body tag.
Frosted Panel is a cross browser solution which allows you to have a full scale, centered, background-image with a responsive, blurry panel overlapping it, of which you can put whatever content you would like inside.
It works by taking advantage of SVG filters, which are supported in most (if not all) browsers, while panning and zooming a duplicate SVG image of the original background-image in order to mimic the actual background-image of the body tag.