I verified this on Mac OS X 10.15(the oficial release version) with FF Nightly 71.0a1(2019-10-08) using the test case from bug 1579534 and I can confirm the fix.
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I verified this on Mac OS X 10.15(the official release version) with FF Nightly 71.0a1(2019-10-08) using the test case from bug 1579534 and I can confirm the fix.