> You forget that tmux is a terminal emulator.

No I don’t forget that.

> can output malformed unicode or escape commands that trigger crashes or code execution, it is actually a huge problem.

I agree.

And to go back to an earlier point, when was the last time you experienced tmux crash? Because I’ve been using it 15 years and yet to see that happen to me.

I get the need to protect against theoretical attacks, but what you’re advocating is throwing the baby out with the bathwater.