Tabbed browser - Archive of obsolete content
you can detect when a tab becomes pinned or unpinned by watching for the tabpinned and tabunpinned events.
... function exampletabpinned(event) { var browser = gbrowser.getbrowserfortab(event.target); // browser is the xul element of the browser that's been pinned } function exampletabunpinned(event) { var browser = gbrowser.getbrowserfortab(event.target); // browser is the xul element of the browser that's been pinned } // initialization var container = gbrowser.tabcontainer; container.addeventlistener("tabpinned", exampletabpinned, false); container.addeventlistener("tabunpinned", exampletabunpinned, false); // when no longer needed container.removeeventlistener("tabpinned", exampletabpinned, false); container.removeeventlistener("tabunpinned", exampletabunpinned, false); detecting tab selection the following code allows you to detect when a new tab is selected in the browser: function ex...

Event reference
tabunpinned addons specific a tab has been unpinned.