javascript - Check if browser supports MutationObserver -

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how 1 write if clause check see if mutationobserver supported?

try using in operator

the in operator returns true if specified property in specified object.

syntax

prop in objectname

parameters

prop

a string or symbol representing property name or array index (non-symbols coerced strings).

objectname

name of object.

if ("mutationobserver" in window) {   // stuff }

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