@gemlog Yeah, it sends EOF to stdin, I think.
For GUI apps it's usually Ctrl+W or Cmd+W on Macs.
This always happens to me when I spend long enough time doing something in the terminal, then switch to Firefox and… Ctrl+Shift+C to copy text — WTF is this?! Inspector! Ctrl+J, Ctrl+H and Ctrl+W no longer work, a-a-argh! 🤬