The ping service from Firebase is using Synchronous XMLHttpRequest which was reported by Google Chrome as follows:
Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. For more help, check http://xhr.spec.whatwg.org/.
The source of this issue is coming from:
.lp?dframe=t&id=612050&pw=gcdpSrzjvk&ns=myapp:5
Is it a bug within Firebase? This isn't causing any issue for now. But in future, browsers may deprecate synchronous XHR.
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