Is there a way to check in chrome is such custom protocol supported

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Javascript

Is there a way to check in chrome is such custom protocol supported without depends on windows blur ?
Is there a way to check in opera is such custom protocol supported ?

What I have tried:

I tried this code but it is not working

window.setTimeout(function () {
try {
iframe.contentWindow.location = "randomprotocolstring://test/";
} catch (e) {
alert("not") ;
}
}, 0);