User Agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64; rv:40.0) Gecko/20100101 Firefox/40.0 Build ID: 20150509081231 Steps to reproduce: Open about:config or other local settings pages, Drag it into another window. Actual results: It creates a new tab in the other window, However it does not load anything and on the original window it remains working until you change to another tab and try to reopen it, At which point the tab is unable to be reopened. Expected results: The tab should be closed on the original window and reopened on the second window.

Please don't touch the Importance (Priority) field. https://bugzilla.mozilla.org/page.cgi?id=etiquette.html ――――――― Mozilla/5.0 (X11; Linux x86_64; rv:40.0) Gecko/20100101 Firefox/40.0 Build ID: 20150510030207 Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:40.0) Gecko/20100101 Firefox/40.0 Build ID: 20150509081231 Browser Console shows Error: Can only swap docshells between browsers in the same process. chrome://global/content/bindings/browser.xml:1076:0