Uncaught TypeError: Cannot read property 'onDidChangeCursorPosition' of undefined

[sciman]

[Enter steps to reproduce:]

1. ...
2. ...

Atom: 1.19.2 x64
Electron: 1.6.9
OS: Mac OS X 10.12.6
Thrown From: typewriter-scroll package 1.0.0

Stack Trace

Uncaught TypeError: Cannot read property 'onDidChangeCursorPosition' of undefined

At /Users/sciman/.atom/packages/typewriter-scroll/lib/typewriter-scroll.coffee:24

TypeError: Cannot read property 'onDidChangeCursorPosition' of undefined
    at Object.toggle (/packages/typewriter-scroll/lib/typewriter-scroll.coffee:24:28)
    at /packages/typewriter-scroll/lib/typewriter-scroll.coffee:9:92)
    at CommandRegistry.module.exports.CommandRegistry.handleCommandEvent (/Applications/Atom.app/Contents/Resources/app/src/command-registry.js:265:35)
    at CommandRegistry.handleCommandEvent (/Applications/Atom.app/Contents/Resources/app/src/command-registry.js:3:65)
    at CommandRegistry.module.exports.CommandRegistry.dispatch (/Applications/Atom.app/Contents/Resources/app/src/command-registry.js:166:25)
    at AtomEnvironment.module.exports.AtomEnvironment.dispatchApplicationMenuCommand (/Applications/Atom.app/Contents/Resources/app/src/atom-environment.js:1338:34)
    at EventEmitter.outerCallback (/Applications/Atom.app/Contents/Resources/app/src/application-delegate.js:334:31)
    at emitThree (events.js:116:13)
    at EventEmitter.emit (events.js:194:7)

Commands

     -1:25.8.0 print-atom:print (div.tool-panel.tree-view)
     -0:50.4.0 styleguide:show (div.tool-panel.tree-view)
     -0:29.2.0 typewriter-scroll:toggle (div.tool-panel.tree-view)

Non-Core Packages

auto-update-packages 1.0.1 
custom-folds 1.9.4 
markdown-preview-plus 2.4.10 
markdown-writer 2.6.5 
open-in 4.0.0 
pain-split 1.4.0 
pandoc 0.2.2 
pandoc-convert 1.1.1 
print-atom 0.1.1 
red-wavy-underline 0.3.3 
save-session 0.15.7 
tablr 1.8.3 
typewriter 0.7.0 
typewriter-scroll 1.0.0 
Zen 0.18.0