We need to be able to configure at runtime which elements on the web page can take focus. This is required so that we can allow users to control whether they want to tab to just form controls, or form controls and links. This configurability should be available in Mozilla, and in embedding applications. Much discussion has gone on in bug 66285 about this and other issues related to tabbing in web content. This bug should cover the implementation of the feature requirement described above.

As an implementation note, I would think we could do this by dynamically generated style based off of prefs, just like we do for underlining links etc.

Surely you mean "tabbable", not "focusable", as I'd expect to be able to click on a focusable element even if it isn't in the tabbing order. A proposal for CSS3 is to have "pointer-focus" and "key-focus" to differentiate between these two cases; we could introduce "-moz-key-focus" to handle this.

Please clarify the difference between tabbable and focussable. If I click on a focussable (but not tabbable) item, does it gain keyboard focus? What happens then if I hit tab -- does focus got to the next tabbable item?

Hm. I would have expected that to be the case, but that doesn't seem to be how native Cocoa controls behave. So it does look like -moz-user-focus: ignore would be consistent with Cocoa.

how does this differ from bug 140612, which was implemented recently on the trunk?

I think this is a dup of 140612, but I'm hesitant to mark it as such unless Simon or Aaron confirm.

Yeah, let's dup this puppy. *** This bug has been marked as a duplicate of 140612 ***

v dup.