I didn't know either! Before I updated it things were a pain in the ass because I was hauling around my birth certificate, marriage certificate, divorce paperwork, and legal name change paperwork, and was constantly having to explain how I got from birth name to current name via marriage but also that I wasn't currently married. It confused everyone when I was like "so here's my legal name change paperwork but the previous name on that doesn't match my birth certificate because it's my married name but I'm not married anymore so here's my married license that shows my maiden name which is what's on the birth certificate and here's my divorce paperwork showing I'm not married anymore". So annoying and I was sick of having to be reminded of my marriage.

Turns out (at least in my state) all it took was sending in a notorized form ($7 at the UPS store), an official copy of my legal name change, and the fee for a new birth certificate (I think like $25). It took about 4 months, but I have a new birth certificate that is identical to my old one in every way, except it has my current legal name on it. Absolutely fills me with joy because now my social security card, passport, drivers license, and birth certificate all match and I'll never have to haul around the rest of that paperwork again. One of my FTM trans coworkers updated his birth certificate and it shows his new name and his gender as male.