Zotero is a firefox add-on for creating bibliographies and managing a database of downloaded papers, articles, etc. When you view an article in your zotero database, an "annotation toolbar" appears near the top of the screen with four buttons "Add annotation", "Collapse all annotations", "Highlight text", "Unhighlight text". The toolbar takes up space, and is not always desired, but you can't remove it. This style solves that problem.

By activating and deactivating this style, you can make the zotero annotation toolbar immediately disappear and appear at will.

Works for Zotero versions 1 and 2.

The style code is just one line, taken from this page: http://forums.zotero.org/discussion/3072/hide-annotation-toolbar/