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HTML 

              
                h1 Inline SVG testing

p After some problems with Modernizr tests I found about SVGRect in this <a href="http://stackoverflow.com/a/28239372/2728847"target="_blank">Stackoverflow answer</a> and I am testing this against Modernizr's test to see which is more reliable.

p I'm using this pen for testing across browsers.

p.modernizr
p.svgrect

svg(viewBox="0 0 200 200" version="1.1" style="width: 100px; height: 100px;")
    circle(cx="100" cy="100" r="80" fill="green" stroke ="darkgreen" stroke-width ="10")
    
p Results:
table(border="1")
  tr
    td: b Browser
    td: b Modernizr
    td: b SVGRect
  tr
    td Chrome 40 for Mac
    td.success Test is successful
    td.success Test is successful
  tr
    td Firefox 36.0.1 for Mac
    td.success Test is successful
    td.success Test is successful
  tr
    td Firefox 35.0.1 for Mac
    td.success Test is successful
    td.success Test is successful
  tr
    td Safari Mac 8.0.2
    td.success Test is successful
    td.success Test is successful
  tr
    td Internet Explorer 11
    td.success Test is successful
    td.success Test is successful
  tr
    td Internet Explorer 10
    td.success Test is successful
    td.success Test is successful
  tr
    td Internet Explorer 9
    td.success Test is successful
    td.success Test is successful
  tr
    td Internet Explorer 8
    td.success Test is successful
    td.success Test is successful
  tr
    td Safari iOS 5
    td.success Test is successful
    td.success Test is successful
  tr
    td Safari iOS 6
    td.success Test is successful
    td.success Test is successful
  tr
    td Safari iOS 7
    td.success Test is successful
    td.success Test is successful
  tr
    td Safari iOS 8
    td.success Test is successful
    td.success Test is successful
  tr
    td Android 2.2 browser<br> Android Simulator on CrossBrowserTesting
    td.success Test is successful
    td.success Test is successful
  tr
    td Android 2.3 browser<br> Android Simulator on CrossBrowserTesting
    td.success Test is successful
    td.success Test is successful
  tr
    td Android 3.2 browser<br> Samsung Galaxy Tab 10.1 (GT-P7500)
    td.success Test is successful
    td.success Test is successful
  tr
    td Android 4.0 browser<br> Android Simulator on CrossBrowserTesting
    td.success Test is successful
    td.success Test is successful
  tr
    td Android 4.1 browser<br> Galaxy Tab 2 on CrossBrowserTesting
    td.success Test is successful
    td.success Test is successful
  tr
    td Android 4.2 browser<br> <a href="http://app.crossbrowsertesting.com/public/iec9d6738c0f1080/livetests/2764871/snapshots/zdabbc2161a2c802588b" target="_blank">Samsung Galaxy S4 on CrossBrowserTesting</a>
    td.fail Test falied
    td.success Test is successful
  tr
    td Android 4.2.2 browser<br> Samsung Galaxy Y TV custom ROM (GT-S5367)
    td.success Test is successful
    td.success Test is successful
  tr
    td Opera Mini 7.6 on Android 4.2.2<br> Samsung Galaxy Y TV custom ROM (GT-S5367)
    td.success Test is successful
    td.fail Test failed
  tr
    td Chrome 40 on Android 4.4.4<br> Moto G 2
    td.success Test is successful
    td.success Test is successful
  tr
    td Android 4.4.4 browser<br> Galaxy S5 on CrossBrowserTesting
    td.success Test is successful
    td.success Test is successful
  tr
    td Android 5.0 browser<br> Android x86 on VirtualBox
    td.success Test is successful
    td.success Test is successful
  tr
    td Blackberry Browser<br> Bold 9900 on CrossBrowserTesting
    td.success Test is successful
    td.success Test is successful
  tr
    td Windows Phone 8
    td.success Test is successful
    td.success Test is successful

  p: b The test is successful when it detects correctly if the browser supports or not SVG.
!

CSS 

              
                body {
  padding: 2em;
}

.success {
  color: green;
}

.fail {
  color: red;
}

table td {
  padding: 8px;
}
!

JS 

              
                var modernizrTest = document.querySelector(".modernizr"),
    svgrectTest   = document.querySelector(".svgrect");

// Modernizr's test
if (Modernizr.inlinesvg) {
  modernizrTest.innerHTML = "<b>Modernizr</b> says that your browser supports SVG. If you see a green circle the test works.";
  modernizrTest.style.color = "green";
} else {
   modernizrTest.innerHTML = "<b>Modernizr</b> says that your browser doesn't supports SVG. If you can't see a green circle the test works.";
   modernizrTest.style.color = "red";
};

// SVGRect's test
if (typeof SVGRect != "undefined") {
  svgrectTest.innerHTML = "<b>SVGRect</b> says that your browser supports SVG. If you see a green circle the test works.";
  svgrectTest.style.color = "green";
} else {
   svgrectTest.innerHTML = "<b>SVGRect</b> says that your browser doesn't supports SVG. If you can't see a green circle the test works.";
   svgrectTest.style.color = "red";
}
!
999px

Console