css - Detect support for -webkit-filter with javascript -

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using javascript, how detect if browser supports webkit filters?

based on info provided @ default css filter values brightness , contrast, have tried following , few of other default values:

 if (window.matchmedia && window.matchmedia("( -webkit-filter:opacity(1) )").matches) {  alert("supported");  }else{  alert("not supported");  }

an relatively easy way test whether css property supported following:

  1. create element
  2. apply css in question element
  3. read value - if same value set in step 2, supported, otherwise not

js:

var e = document.queryselector("img"); e.style.webkitfilter = "grayscale(1)"; if(window.getcomputedstyle(e).webkitfilter == "grayscale(1)"){    "supported!"; }

see example


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