philc/vimium — pull request #1355 by mrmr1993 (2014-12-18 11:03:48+00:00)
Title: Stop link hints from overlapping and detect clickable elements on google inbox

This PR
* rewrites the link hints XPath as DOM code, giving better accuracy and readability
* detects overlapping clickable elements and attempts to find locations where they do not overlap to place a link hint
- this requires elements to be in the order they appear in the DOM, another reason for using the DOM rather than an XPath
* integrates a variation on PR #1316 to detect clickable elements on google inbox
* allows for multiple images to use the same `` to provide clickable regions
* add support for `` in image maps (previously the code assumed everything was a rectangle)
* document the fact that we don't properly support `` in image maps
* support clicking `opacity: 0` elements: some websites (notably Facebook) use these to provide the functionality of less attractive elements (eg. ``) while showing an image behind that appears to the user to be the actual button.

This fixes #1307.