Created attachment 207194 [details]
Debug file with possible showing why happening this problem

Dear Developers,

If I opening Orca GUI preferences dialog, navigate a dialogue widget, goto back the actual page tab and press left or right arrow key, the caret land a dialogue widget, not the prewious or next page tab.
I experienced this issue with Ubuntu 12.04, both Orca 3.5 and actual master version.

Reproducation steps:
1. Click preferences button in Orca main window, or press Orca Modifier+Space key.
2. When the dialog pops uop, you land the general page, this situation arrow keys navigation switch right between page tabs. Press a tab key to jump a dialog widget.
3. If you press one tab key, this is enough. Press SHIFT+TAB key combination, and try now switch between page tabs with arrow keys. If press right arrow, you will be jump near middle a dialog widget (for example in general page the speak under mouse check box), not voice page.

CTRL+ALT+PAGEUP and CTRL+ALT+PAGEDOWN key combinations always working right.
I attached the debug.out file, hopefuly showing why happening this problem and this is not a GTK3 bug.

Attila