Way back in the learning curve, sometimes (embarrassingly, quite a few times
When I come across them now, I can’t enter their sex in the Property Box because the space to enter it isn’t there.
If I’m entering new people, it seems to be OK while the program is open, but after closing and then reopening FH, the M or F choice in the Property Box has disappeared.
There is a workaround where I create a spouse for the person, which brings up a box asking for their sex and afterwards I just delete the blank spouse record.
This also happened in v4 and although it's no big deal, I just wondered why the ‘Sex’ menu disappears.