Yes they do. I watched a Breaking the Faith series showing some kids escaping from their compound in Utah and one of the big things for them was wearing 'gentile' clothing in tje end because they took off their garments as well as their long dresses.
I think their garments are longer in the legs, like ankle length but don't quote me on that. It was a year since I watched it.
Yes, they do. Full-length ones. In the St. George sun.
Imagine the church in the 1880's, with the rules -- long garments, prairie dresses, alcohol and coffee are okay -- exported to modern times. You've captured the essence of the FLDS. No calf or forearm can show, but coffee and wine are okay.
The mainstream LDS Church did not authorize "short" (as in short sleeves with leg hems just above knee) for street use until the mid 1920s. Before that, all garments were down to wrists and ankles. The old style garments, however, were required for temple use into the early 1970s. Board member Stray Mutt posted years ago about having to wear long garments for his pre-mission live endowment
You've already gotten your answer, but here's the really funky part....
When I was a wee girl, I loved going through my mommies lingerie drawer. ('Mainstream' LDS) She had a pair of "old lady's garments". They had ties down the front, arms down to just below the elbow - maybe all the way to the wrist, open in the crotch for 'taking care of business', and all the way down to the ankle. And it was ALL one piece. It was not the 'slip on' style that I was used to seeing her wear - the ones that you stepped into via the neck.
There were the normal markings on the breasts, belly, and knee. But, there were other markings on the right elbow (I don't remember anything for sure on the wrist... but there may have been. ANYONE old enough to remember?), and another on the left ankle.
The two-piece (non step in style) was authorized in the 1970s. By then, long garments were no longer required for temple use. So it may very well be that no two-piece long style models were ever produced. They still make one piece step-in styles, but with short sleeves and legs.
Growing up Never-Mo, the first garments I ever saw were short two piece numbers worn by my intern during my residency training (eight of us shared a bunk room with four bunk beds during residency training).
Some groups have their own temple and other smaller groups meld into the mainstream wards and have regular TRs.
When my parents were following a polygamous prophet, they wore long garmies to their wrists and ankles. The prophet had shorter than average arms which made his garments always visible sticking out beyond his shirt cuffs. They were filthy looking dark gray, never white.
If you're familiar with "Unbreakable Kimmy Schmidt," you're familiar with how the "Mole Women" were dressed as FLDS. If you're familiar with all episodes, you might remember one where Kimmy Schmidt was wearing long garments, too.