I'm trying to update BarTab so that the "select nearest loaded tab" option works
as expected in post-3.x versions of Firefox. This mainly means making it work as
expected with Panorama.

I've already gotten most of it working, but I still get unexpected behavior when
moving the current tab to a different tab group, via the tab context menu's
"Move to Group" sub-menu. In order to correct that, I need to be able to respond
when such a move happens.

BarTab responds to tab closings by listening on the TabClose event, via
tabContainer.AddEventListener(). The obvious thing to do would be to add another
listener, with an appropriate event; however, looking at the MDN "Mozilla event
reference" page, I do not see any apparent event which seems like it would fire
on "tab move to group".

(Based on what I've learned about the apparent underlying implementation of tab
groups, I suspect that "move tab to new group" is currently implemented simply
as "move tab to new offset in the current window's tab list", which - in the
absence of tab groups - doesn't seem like that the sort of thing that would need
an event. That would explain the lack, but it doesn't really help me even if
true.)

How can I hook in to respond when a tab is moved to a new tab group?

--
       The Wanderer

Warning: Simply because I argue an issue does not mean I agree with any
side of it.

Every time you let somebody set a limit they start moving it.
   - LiveJournal user antonia_tiger