Depends on how much backstory you've fleshed out It's ok to have a short one. Most of my backstory a are about three paragraphs long detailing where my character was born and raised/childhood in the first one, what they've done for work or where they've trained as an adult in the second, and where they started RPing in the third. You can always edit these as you go and as long as you haven't cemented your backstory ICly you can always change it, no one pays that much attention.
Also some people completely forgo the backstory in favor of an extensive personality template although I'm not sure why.
It really depends on the character to be honest. Sometimes I like to leave things more vague because I don't have as clear a vision for the character, and would like to leave development more to actual roleplay. Other times I've got a ton of backstory laid out and just have to corral a flock of hyperactive chickens (thoughts) into a cohesive biography, to still leave room for growth in the RP. I like both vagueness and detail.
I will completely forgo making any character backstory whatsoever if I can help it, but when and where profiles are a requirement, I tend to start brief and somehow end up slogging out paragraphs within paragraphs. This is usually a result of putting music on when I begin typing, because when that starts, it doesn't end until the music stops.
But I am a fergegackabar of a firm believer in leaving character development to actual roleplay. I don't know about others, but I spend more time peeing than I do reading other people's profiles, and though I drink a lot of water, and thus in turn pee quite a bit on a given day, it's nowhere near enough to how little time I spend reading other people's profiles. I would fret not if someone treated my profiles the same way.
Someone may correct me if I'm wrong, but unless the profile information is significantly...significant...you could always just say "Oh well that part of the history didn't actually change IC because you see the profile was actually based on an in-universe database profile and it was never updated by the NPC handlers ha hah ah hahahaaa ahahaha aha"
Also, that Baelish gif... Well, that Baelish gif. Nuff said.