in extreme cases, detach from their nailbeds or fall off entirely
The article is on a site with a lot of advertising and it does not explicitly state or reference an example of an astronaut who actually lost a finger nail due to any cause, so not sure how accurate any of it is. The articles title is Spacesuit Gloves Can Make Astronauts' Fingernails Fall Off with Can being an operative word suggesting it could happen, but not that it ever has.
Do astronauts lose finger nails in space? Are there any verified occurrences? If so is it still an issue?