Guardian has open sourced a framework for managing content editable

[Ian Mulvany]

repo: https://github.com/guardian/scribe

example: http://guardian.github.io/scribe/

article: http://www.theguardian.com/info/developer-blog/2014/mar/20/inside-the-guardians-cms-meet-scribe-an-extensible-rich-text-editor 

documentation of browser inconsistencies: https://github.com/guardian/scribe/blob/master/BROWSERINCONSISTENCIES.md