In a new iOS Safari tab go to a tweet (e.g. twitter.com/user/status/something) and then add it to Reading List and check that the Reading List entry takes you to the tweet.
Now hit the profile picture of the tweeter, sending you to their profile page and then bring up the Reading List–the Reading List entry will now point to the Profile page, not the original tweet.
This is also true if the tweet you originally save is something like a retweet with comment and you click the tweet they were retweeting–it will replace what you originally saved in Reading List. You can then continue this by clicking on that tweet’s profile pic and the Reading List entry will get changed again. I’ve been able to keep this going for many steps.
This does not happen with links in tweets that cause Safari to open a new tab.
Anyone else seeing this? I haven’t been able to make it happen with sites other than Twitter (yet at least).
(I’m running iOS 13, but think this bug may have been around longer…but I only just got around to actually reproducing it)