I'm having quite a few issues in the latest (and previous) versions of Sitefinity when I'm creating new items in the admin area and using the lightbox forms which are on the front end editing screens.
e.g. Going to Page Templates -> Create Template the whole screen goes blank. If I resize the screen then the content shows and I can create a new item.
I get a similar issue on the front end (screenshot attached) and sometimes I can resize the screen and the content shows but most of the time it doesn't.
This seems to be mainly in Chrome as it works in Firefox but I don't use Firefox for the main development browser.
I'm using Windows 8.1, Chrome and it's a hDPI screen on my laptop and HD monitor on the external screen. It doesn't matter which window I have this open on , it seems to be the same issue