--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -4820,17 +4820,17 @@ pref("dom.w3c_pointer_events.enabled", f
 
 // W3C pointer events draft
 pref("dom.w3c_pointer_events.implicit_capture", false);
 
 // W3C draft ImageCapture API
 pref("dom.imagecapture.enabled", false);
 
 // W3C MediaDevices devicechange event
-pref("media.ondevicechange.enabled", false);
+pref("media.ondevicechange.enabled", true);
 
 // W3C MediaDevices devicechange fake event
 pref("media.ondevicechange.fakeDeviceChangeEvent.enabled", false);
 
 // W3C touch-action css property (related to touch and pointer events)
 // Note that we turn this on even on platforms/configurations where touch
 // events are not supported (e.g. OS X, or Windows with e10s disabled). For
 // those platforms we don't handle touch events anyway so it's conceptually