It is now possible to map XPath expression that points to an attribute to a file chooser. Pointing to a tag will still automatically pick first src attribute from that tag when mapping to a file chooser.
Merging 7.6 to 7.8

* 7.6:
  It is now possible to map XPath expression that points to an attribute to a file chooser. Pointing to a tag will still automatically pick first src attribute from that tag when mapping to a file chooser.