[EPUB3 export] Use pop-up footnotes doesn't work

Hello!

When I check the "use pop-up footnotes " option, the epub file doesn’t really have pop-up footnotes in it.

I also tried unchecking the option, but XHTML files inside epub are the same.

“A” tag lacks this attribute: epub:type=“noteref”

Maybe it’s not implemented yet? I use Version: 2.9.9.6 Beta (937253) 64-bit - 26 May 2020

Thanks!