User Agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20100101 Firefox/17.0 Build ID: 20121128204232 Steps to reproduce: I opened a new private window and opened some tabs and all seemed normal. I have tried to reproduce it again but I can't, so I don't know what exactly causes the bug. Actual results: I realized that the private button was overlapping the first tab. Expected results: It shouldn't be overlapping the first tab.

Confirmed and setting to NEW STR: 1. Make sure browser is maximized on Windows (tested using win7 x64) 2. close browser 3. Open browser 4. Ctrl+Shift+P or AppMenu -> Open PB window 5. Note the APPMenu button overlaps the first tab. Closing/Reopening PrivateBrowsing Window will now show in proper place. It ONLY occurs on initial start-up of browser in Maximized View and first launch of PB Window.

Hmm, Dao, do you have any idea how this could be happening? Don't we just let the tabs flow on the right-hand side of this button?

This is happening because the button size changes after tabs have been put in the title bar.

(In reply to comment #3) > This is happening because the button size changes after tabs have been put in > the title bar. Do you know what the best way to fix it is?

Ehsan, can you test this on Windows? I believe this should do it.

Comment on attachment 700124 [details] [diff] [review] patch No, it doesn't, the icon doesn't even show up with this patch. If I change the browser.css hunk to use list-style-image with the original selector and use the new selector to only set the width and height, the icon shows up but the bug happens as it does in an unpatched build.

Ugh, menu buttons have an extra layer of inner boxes :/

Comment on attachment 700532 [details] [diff] [review] patch Yeah, this fixes the bug. Thanks!

(Just as a reminder, please nom this for Aurora as well.)

Comment on attachment 700532 [details] [diff] [review] patch [Approval Request Comment] Bug caused by (feature/regressing bug #): bug 749394 User impact if declined: See comment 0 Testing completed (on m-c, etc.): locally Risk to taking this patch (and alternatives if risky): not very risky String or UUID changes made by this patch: none

Verified in Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20130113 Firefox/21.0 ID:20130113031019

Mozilla/5.0 (Windows NT 5.1; rv:20.0) Gecko/20100101 Firefox/20.0 Mozilla/5.0 (Windows NT 6.1; rv:20.0) Gecko/20100101 Firefox/20.0 Verified as fixed using STR from comment 0 and comment 1 on Firefox 20 beta 1 (buildID: 20130220104816), latest Aurora (buildID: 20130220042017) and latest Nightly (buildID: 20130221030952).

Verified as fixed on Firefox 21 beta 2 (build ID: 20130401192816) Mozilla/5.0 (Windows NT 5.1; rv:20.0) Gecko/20100101 Firefox/20.0