user-keys do not work in a popup?

[097115]

That's probably by design (due to some limitations of display-popup?) but just wanted to confirm I'm not doing anything wrong:

1. tmux -L test -f /dev/null
2. tmux -L test set -s user-keys[0] "^[q" (entered as <C-v><M-q>)
3. tmux -L test bind -n User0 send-keys qq
4. Press <M-q>, observe "qq", so far so good.
5. Now, tmux -L test display-popup -E bash
6. Press <M-q>, observe nothing (and no bell either).

Is this expected? :)