Copy (quill) paste (MS word) loses formatting

[KameSama]

[Describe the issue]
When copy pasting (from quill to MS Word), it loses the formatting ( bold, italic etc...).
Steps for Reproduction

1. Visit http://beta.quilljs.com/
2. Change a word to bold
3. Copy it and paste it in a word processor

Expected behavior: [expected]
The formatting (common) should be kept
Actual behavior: [actual]
The formatting is lost
Platforms: [ex. Chrome 48 on Mac 10.11]
Chrome 51
Version: [version]
v1.0.0-beta.4

[KameSama]

Important note : When the "editablecontent" attribute is set to false (<div class="ql-editor" contenteditable="false">) ; the copy with format works as expected.