Interesting observation from being bored. On Twitter Web, you can go to a person's page with https://twitter.com/ {username}, but clearly some keywords were reserved early on...

Like the "user" messages, which, https://twitter.com/messages  will just take you to your DMs

https://twitter.com/notifications  = Your notifs
https://twitter.com/explore  = Explore...

You get it.

BUT... hehe butt, but https://twitter.com/bookmarks  doesn't take you to your bookmarks, it takes you to the profile of whoever got that username all the way back in April 2007

That's about a year after Twitter was created but that's besides the point.
The point of this thread is that your bookmarks live on https://twitter.com/i/bookmarks  and that just may be because someone got the handle early on. I dunno. But it's interesting.