The preview option in the new floating editing toolbar (need's autosave extension) is not shown if you scroll the web-page to the top.

Steps to reproduce

1. Activate the autosave extension
2. Create an Article on the Admin interface
3. Verify that on top right, in the toolbar, there is a preview option
4. Scroll all the way up
5. Verify that the edit tool-bar changes from the top of the screen to a default position
6. Verify that the preview option is no longer visible