Comment 37 for bug 481541

(In reply to comment #35)
> Is our user expecting this setting to affect these tabs mentioned just 1 cm up
> in the same dialog or is our user expecting this pref to affect tabs opened by
> middle-clicking; a hidden pref in Firefox? Hmmmm.

I saw the same potential confusion and my solution is the second attached patch.
The problem, of course, is that this is inconsistent with previous builds, as we
have now changed the meaning of the option.

> It seems to me that we should shift the generically named
> browser.tabs.loadInBackground pref over to left-click and external-URL duty and
> invent a new hidden pref for dealing with the (now) less visible middle-click
> tabs. All you gotta do then to make the external-URL default the way you want it
> is remove the Firefox override.

I disagree, I think the prefs should stay the same and we use the new
browser.tabs.loadDivertedInBackground (or something) to regulate diverted links.
The reason for this is the loadInBackground pref doesn’t just regulate middle
click links, but links opened by the right click command “Open in new Tab” – the
most obvious/logical means to open links in tabs to the user (especially new
users). Furthermore, it is inconsistent with previous builds and will be
confusing for returning users.

> This is complicated by the fact that the external URL and diverted left-click
> tabs aren't quite the same thing, but we've never considered giving them
> separate focus prefs.

Agreed. Bradley proposed the best option for doing this in comment 14. The
problem is, this solution breaks the current tab option UI.