Hyper doesn't correctly support mouse mode in tmux 2.5

• I am on the latest Hyper.app version
• I have searched the issues of this repo and believe that this is not a duplicate

• OS version and name: OSX 10.12.5
• Hyper.app version: Version 1.3.3 (1.3.3.1754)
• Link of a Gist with the contents of your .hyper.js: Vanilla install, no customisation.
• Relevant information from devtools (CMD+ALT+I on Mac OS, CTRL+SHIFT+I elsewhere): N/A
• The issue is reproducible in vanilla Hyper.app: Is Vanilla

Issue

Mouse mode in tmux 2.5 (stable) does not appear to function.

Steps to reproduce (from clean install of all tools)

1. Install Hyper
2. Install tmux via brew install tmux
3. Configure tmux to use mouse mode by echo "set -g mouse on" >> ~/.tmux.conf
4. Run tmux
5. Inside a tmux session run tmux split-window

Expected behaviour

You should be able to use the mouse to select which pane within the tux session is active.

Actual behaviour

No effect. It does not allow mouse interaction with panes in tmux, and no obvious logging is produced within Hyper to indicate an error.

I've validated this functions as expected in Terminal.app and iTerm with same config and installation steps.

Start by reproducing the issue in Hyper with tmux 2.5 and set -g mouse on, following the listed split-window steps. Compare mouse pane selection with Terminal.app or iTerm; done means mouse interaction works within tmux panes without errors.