This test is for https://bugs.webkit.org/show_bug.cgi?id=24427 and can be used to demonstrate that tooltips can appear even when mouse is not directly over the target element.
This test assumes you are in a clean browser window (no existing tabs open) and you have hidden the tab bar. To hide the tab bar, select View->Hide Tab Bar.Follow these steps to reproduce:
To repeat this test, close the tab that was opened as a result of this test, and follow steps 2 thru 4.
Once you have observed the issue you will find that you can take some liberties in following the aforementioned instructions (i.e. the positioning of the mouse when selecting Open Link in New Tab). Also, you can substitute step 3 for "Right click on the hyperlink 'Hover over me', select Open Link in New Window and do not move the mouse. Close the newly created window using the keyboard shortcut Cmd-W."