Check if app.dock exists before using it. Fixes #208, #210, #228, #231.
Check if app.dock exists before using it. Fixes #208, #210, #228, #231.

railsware/upterm,drew-gross/black-screen,vshatskyi/black-screen,j-allard/black-screen,vshatskyi/black-screen,black-screen/black-screen,j-allard/black-screen,railsware/upterm,black-screen/black-screen,drew-gross/black-screen,drew-gross/black-screen,shockone/black-screen,j-allard/black-screen,vshatskyi/black-screen,black-screen/black-screen,vshatskyi/black-screen,shockone/black-screen,drew-gross/black-screen