1. Log into the website
  2. View any unblocked user's profile
  3. Block this user
  4. Immediately swap pages to another unblocked user's profile (using the friends list works)
  5. Note the block icon persists on the new username, and the drop-down for the block feature still says "unblock"
There is nowhere to report website bugs and this has been a problem for months now.
This behavior is noticed on both Google Chrome/Windows and Safari/iOS.