Backspace Issue on Safari

[scottmessinger]

When the cursor is at the beginning of the line and you press backspace, the character is deleted and the cursor moves to the previous line

Video:
http://cloudapp.commoncurriculum.com/2S2a1U310q3c/Screen%20Recording%202016-09-07%20at%2012.29%20PM.mov

Steps for Reproduction

I used quill.getContents() to get the contents of the editor which, hopefully, will help in debugging:
https://gist.github.com/scottmessinger/2550d4a2f700dcfd89f53048c7fd0c8e

Expected behavior: [expected]
Moves the line to the previous line

Actual behavior: [actual]
See Video:
http://cloudapp.commoncurriculum.com/2S2a1U310q3c/Screen%20Recording%202016-09-07%20at%2012.29%20PM.mov

Platforms:
Safari Version 9.1.2 (11601.7.7)

Version: [version]
The version on the quilljs.com homepage.