STR: 1. Open a window using: window.open("http://www.mozilla.org/", "_new", "height=500&width=500") 2. Try to read the page title from the top of the window AR: no page title nor icon ER: page title and icon, as on Nightly AFAICT this is because in updateTitlebarDisplay, we're now only using gInPrintPreviewMode to determine whether to show the titlebar and change the chrome margins. I believe this also causes some of our test failures, eg. the queryCaretRectWin failures in mochitest-other (chrome).
Created attachment 751012 [details] [diff] [review] Patch I believe the original removal of the window.menubar.visible bits was a mistake (as these are barprops and don't necessarily say anything about whether the actual XUL element is visible), so I've more or less changed that back (although calling it displayAppButton didn't make sense so I've called it drawInTitlebar instead). I *have* left out the check whether the menubar is autohidden, which I guess won't make sense anymore. This fixes the issue I was seeing. It also fixes the test I was originally looking at (test_queryCaretRect), as a side-effect.
Comment on attachment 751012 [details] [diff] [review] Patch Since this isn't about the app menu button anymore, it's unclear to me why this behavior should depend on window.menubar.visible. I believe you should use window.toolbar.visible. That's what tabbrowser uses to hide the tab bar in popups.
Created attachment 751057 [details] [diff] [review] Patch v2 OK. This works just as well in a quick test, so here we go...
Not reproducible locally (05/17 Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20130517 Firefox/24.0).