Thanks for all the comments. If anyone is still experiencing this issue after upgrading to the latest version of Chrome, I want to know about it! Feel free to send me an email at email@example.com
Our team experienced this (HTML Source Editor being blank), and solved it by clearing our browsing data. I can't speak to needing to upgrade Chrome and that being the source of problems, but I'd try clearing out the cache/browser data in addition to anything else you're trying.
Out of curiosity, are we all using Macs?
I'm using a Mac and Chrome 43.0.2357.81, but the rest of my team uses Windows PCs.
Since clearing our caches, none of us have had this issue (thankfully).
Chrome update seems to have fixed it. I do use a Mac, though.