<A href=...> elements with visibility: hidden are still 'there': they can still be navigated, still generate events (e.g. mouse over, etc.). It doesn't matter if the element is made invisible by a style sheet or dynamically by a script, nor does it matter if the visibility is inherited from a parent. I first noticed this in M12 and it still exists in M13. I have classified this as major since many sites rely on hidden elements not being navigable/firing events, and the spurious events could severly hamper user interaction on dynamic sites.

Tom, event problem. Pretty sure it's a DUP

yeah, dupe of 12232 *** This bug has been marked as a duplicate of 12232 ***

Marking verified dup of 12232.