• nvim --version: v0.3.0-1304-gf711b6351
• nvim v0.2.2 behaves differently
• Operating system/version: Fedora 28
• Terminal name/version: tmux/mosh/hterm.js
• $TERM: tmux-256color

The clipboard provider has lost the ability to access /dev/tty which is needed for OSC 52. So my clipboard provider worked in 0.2.2 and no longer works in 0.3.0

Steps to reproduce using nvim -u NORC

This is just a demonstration of losing /dev/tty not really the clipboard provider which is more involved.

nvim -u NORC
!!echo hi > /dev/tty

Actual behaviour

/bin/bash: /dev/tty: No such device or address

Expected behaviour

Well, this reproducer actually makes some garbage in the terminal in 0.2.2, and no error message. But the important part is that the clipboard provider doesn't have access to /dev/tty either.