I can break the navigation toolbar with the following STR: STR: 1. Open Firefox with a new Tab or default start page 2. Enter customization mode (via menu panel) 3. Duplicate the customize tab at least 3 times 4. Click on the first tab (new tab / start page) 5. Click into the customize tab 6. Click on the menu button (to leave the customize mode) Actual: The navigation bar is completely broken: Every element is lost. Expected: The customization tab should be closed (without breaking).

taking this to Australis M7 Note: should we dis-allow customize tab duplication?

Removing the items from M7 that do not block us from landing on m-c.

I think a user has to be pretty deliberate at cloning the customization tab, so P3. But can this also break if you enter customize mode in separate windows?

(In reply to Justin Dolske [:Dolske] from comment #3) > But can this also break if you enter customize mode in separate > windows? I can't break it anymore with my own STR. I even tried to break it with 'about:customizing' in different windows. The only thing happening with the STR is Firefox leaves the Customization mode and shows 'about:customizing' in the URL. But I assume that is ok, since this is really rare case. Maybe someone can verify that the STR is not valid anymore?

(In reply to Morpheus3k from comment #4) > (In reply to Justin Dolske [:Dolske] from comment #3) > > But can this also break if you enter customize mode in separate > > windows? > > I can't break it anymore with my own STR. I even tried to break it with > 'about:customizing' in different windows. > The only thing happening with the STR is Firefox leaves the Customization > mode and shows 'about:customizing' in the URL. > But I assume that is ok, since this is really rare case. > > Maybe someone can verify that the STR is not valid anymore? Are you using an add-on to duplicate tabs? What happens when you hit enter on the about:customizing URL after exiting customization mode? :-)

No, I duplicate the tabs via Drag + 'Alt' (on OS X). When I hit enter, Firefox transforms into the customization mode. If I close the customization mode via 'Customize' or the Menu Panel, Firefox animates the customization mode back to the normal Firefox window. Afterwards it closes the tab on the tabstrip and switches to the next tab. If this tab is a customization tab, it won't transform, but shows 'about:customizing'. If I close the customization mode via 'Tab close' (hitting Cmd + W or the Tab's close button), Firefox closes the tab and switches to the next tab. This time it does not animate anything, if the next tab is another customization tab. Short STR: 1. Open UX 2. Enter customization mode via Menu Panel 3. Duplicate the customization tab at least once 4. Switch to the last customization tab 5. Close the customization tab via Menu Panel or clicking on 'customize'

(In reply to Morpheus3k from comment #6) > No, I duplicate the tabs via Drag + 'Alt' (on OS X). You learn something new every day - I didn't know we had that functionality! > When I hit enter, Firefox transforms into the customization mode. OK, good! :-) > If I close the customization mode via 'Customize' or the Menu Panel, Firefox > animates the customization mode back to the normal Firefox window. > Afterwards it closes the tab on the tabstrip and switches to the next tab. > If this tab is a customization tab, it won't transform, but shows > 'about:customizing'. > > If I close the customization mode via 'Tab close' (hitting Cmd + W or the > Tab's close button), Firefox closes the tab and switches to the next tab. > This time it does not animate anything, if the next tab is another > customization tab. > > Short STR: > 1. Open UX > 2. Enter customization mode via Menu Panel > 3. Duplicate the customization tab at least once > 4. Switch to the last customization tab > 5. Close the customization tab via Menu Panel or clicking on 'customize' OK, so there's no more full-on breakage of the navbar here, so I'm downgrading this to a P4. Ideally we should still fix this, and it might be fixed as part of bug 889120.

I believe this is "fixed" by the fix for bug 860648, which should mean you can no longer duplicate the tabs by dragging.