What exactly is the purpose of these things ?
I ran into this particular problem on a house remodel about a year ago, when 2 inspectors I had to deal with insisted the recep wasn't functioning correctly because their tester wouldn't trip it.
I told them both that GFI testers, including my fancy adjustable Hubbell will not not work on ungrounded GFIs, I also tried telling them that the only way to properly test a GFI is with the test button on the device since most homeowners probably don't have a tester, but they both told me to fix it by adding a ground or , as one guy said, "just put a 2 wire outlet there"
So I wonder why we need these things since the tester needs a ground to trip the GFI, while accompanying install paperwork only calls for attaching a ground if one is available
