BUG ID: Bugzilla bug 8295 Dictionary pop-up panel targets the wrong word in a scrolled IFRAME

STEPS TO TEST:
1. Click the inner frame’s down scroll arrow once.
2. Move the mouse pointer over “target”.
3. Press Command-Control-D to invoke the Dictionary pop-up panel.

TEST PASS: The Dictionary pop-up panel will appear over “target”, giving its definition.

TEST FAIL: The Dictionary pop-up panel will appear over “failure”, with the definition of failure.