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new tab appears at startup, cannot close


Occasionally, a new tab will open when starting Firefox in Windows 7 or Ubuntu 12.10. This opens to the default new tab page for Firefox, which I have set to about:blank. This tab cannot be closed by left clicking the "x", by right clicking and selecting close tab from the context menu, or with "Ctrl+W". Additionally, switching between tabs with "Ctrl+Tab" and "Ctrl+Shift+Tab" skips over this tab. It behaves as if it is already closed, but improperly. I suspect it MAY be because it was loaded before the other tabs, pinned or home, as part of the normal start up procedure, but never closed, but it appears to the right of my home page tab, not the left. I would attempt to visit a website on this ghost tab to get it unstuck, but even clicking on it isn't working. As I recall, it is selected at startup, so I may be able to try that again the next time it happens. That isn't a guaranty, though, and there is also the possibility that Firefox will simply crash when I attempt to visit a webpage, as it appears to be improperly closed.

Chosen solution

I haven't seen this bug in a while, I'm going to call it solved. My guess is it was an addon, and the developer caught on and fixed the bug in time for their latest version. I see that some of my addons haven't updated since I posted this bug report (some of them in the last year), so if I see the bug again, I'll just manually update addons on another machine until I can reproduce it. Then I'll tell the developer and post it here, if anyone's interested.

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Additional System Details

Installed Plug-ins

  • Shockwave Flash 11.7 r700
  • Google Update
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.6
  • 5.1.20125.0
  • NVIDIA 3D Vision plugin for Mozilla browsers
  • NVIDIA 3D Vision Streaming plugin for Mozilla browsers
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • Logitech Device Detection
  • Version 1.1.11, copyright 1996-2011 The VideoLAN Teamhttp://www.videolan.org/
  • Windows Presentation Foundation (WPF) plug-in for Mozilla browsers
  • np-mswmp


  • Firefox 20.0.1
  • User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:20.0) Gecko/20100101 Firefox/20.0
  • Support URL: http://support.mozilla.org/1/firefox/20.0.1/WINNT/en-US/


  • Adblock Plus 2.2.3 ({d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d})
  • Add-on Compatibility Reporter 2.0 (compatibility@addons.mozilla.org)
  • Charset Switcher 12.0.20120501 (charsetswitcher@moztw.org)
  • Cheevos 1.4 (jid1-bpzDizt9E1R7nw@jetpack)
  • Collusion 0.27 (jid1-F9UJ2thwoAm5gQ@jetpack)
  • Destroy the Web 1.2.2 ({7BDB48D1-CD94-4B99-A5A4-E418B9EE6532})
  • Direct Torrent Downloader 1.0.3 ({8d273bc4-4326-cbdd-c872-f82eecc95a5c})
  • DoNotTrackMe (donottrackplus@abine.com)
  • Download Statusbar 0.9.10 ({D4DD63FA-01E4-46a7-B6B1-EDAB7D6AD389})
  • Expire history by days 1.1 (expire-history-by-days@bonardo.net)
  • FabTabs 1.5.2 (fabtab@captaincaveman.nl)
  • feedly 14.0.482 (feedly@devhd)
  • Firebug 1.11.2 (firebug@software.joehewitt.com)
  • Flagfox 4.2.8 ({1018e4d6-728f-4b20-ad56-37578a4de76b})
  • FlashGot ({19503e42-ca3c-4c27-b1e2-9cdb2170ee34})
  • Ghostery 2.9.4 (firefox@ghostery.com)
  • How Many Times Can I Back? 0.2.2011012001 (historycounter@piro.sakura.ne.jp)
  • HTTPS-Everywhere 3.1.4 (https-everywhere@eff.org)
  • Image Zoom 0.5.2 ({1A2D0EC4-75F5-4c91-89C4-3656F6E44B68})
  • Informational Tab 0.4.2012122901 (informationaltab@piro.sakura.ne.jp)
  • InvisibleHand 3.8.28 (canitbecheaper@trafficbroker.co.uk)
  • Load Tabs Progressively 1.6.1 (loadTabsProgressively@ithinc.cn)
  • Logitech Device Detection (DeviceDetection@logitech.com)
  • Microsoft .NET Framework Assistant 0.0.0 ({20a82645-c095-46ed-80e3-08825760534b})
  • Morning Coffee 1.35 (morningCoffee@shaneliesegang)
  • NetVideoHunter 1.9.5 (netvideohunter@netvideohunter.com)
  • Personas Plus 1.7.1 (personas@christopher.beard)
  • Personas Rotator 7.1 ({6e73f6b7-b9ab-44b8-b744-6393e3c2e351})
  • Pocket 3.0.1 (isreaditlater@ideashower.com)
  • Resurrect Pages 2.0.6 ({0c8fbd76-bdeb-4c52-9b24-d587ce7b9dc3})
  • RetailMeNot 2.4 (enquiries@retailmenot.com)
  • SkipScreen 0.7.0 (SkipScreen@SkipScreen)
  • SmoothWheel (AMO) ({5F590AA2-1221-4113-A6F4-A4BB62414FAC})
  • TinEye Reverse Image Search 1.1 (tineye@ideeinc.com)
  • Troubleshooter 1.1a (troubleshooter@mozilla.org)
  • Zotero 3.0.11 (zotero@chnm.gmu.edu)
  • ColorfulTabs 18.5 ({0545b830-f0aa-4d7e-8820-50a4629a56fe}) (Inactive)


  • incrementalGCEnabled: True


  • adapterDescription: NVIDIA GeForce GTX 660
  • adapterDescription2:
  • adapterDeviceID: 0x11c0
  • adapterDeviceID2:
  • adapterDrivers: nvd3dumx,nvwgf2umx,nvwgf2umx nvd3dum,nvwgf2um,nvwgf2um
  • adapterDrivers2:
  • adapterRAM: 2048
  • adapterRAM2:
  • adapterVendorID: 0x10de
  • adapterVendorID2:
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  • directWriteEnabled: True
  • directWriteVersion: 6.2.9200.16492
  • driverDate: 1-18-2013
  • driverDate2:
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  • isGPU2Active: False
  • numAcceleratedWindows: 1
  • numTotalWindows: 1
  • webglRenderer: Google Inc. -- ANGLE (NVIDIA GeForce GTX 660 )
  • windowLayerManagerType: Direct3D 10

Modified Preferences

  • accessibility.typeaheadfind.flashBar: 0
  • browser.cache.disk.capacity: 358400
  • browser.cache.disk.smart_size.first_run: False
  • browser.cache.disk.smart_size.use_old_max: False
  • browser.cache.disk.smart_size_cached_value: 358400
  • browser.history_expire_days.mirror: 180
  • browser.places.importBookmarksHTML: False
  • browser.places.smartBookmarksVersion: 4
  • browser.privatebrowsing.dont_prompt_on_enter: True
  • browser.sessionstore.restore_on_demand: False
  • browser.startup.homepage: about:home|https://www.google.com/
  • browser.startup.homepage_override.buildID: 20130409194949
  • browser.startup.homepage_override.mstone: 20.0.1
  • browser.tabs.onTop: False
  • browser.tabs.warnOnClose: False
  • dom.disable_window_move_resize: True
  • dom.event.contextmenu.enabled: False
  • dom.mozApps.used: True
  • dom.w3c_touch_events.expose: False
  • extensions.checkCompatibility: False
  • extensions.checkCompatibility.10.0: False
  • extensions.checkCompatibility.10.0a: False
  • extensions.checkCompatibility.11.0: False
  • extensions.checkCompatibility.11.0a: False
  • extensions.checkCompatibility.12.0: False
  • extensions.checkCompatibility.12.0a: False
  • extensions.checkCompatibility.3.6: False
  • extensions.checkCompatibility.3.6.previous: False
  • extensions.checkCompatibility.3.6b: False
  • extensions.checkCompatibility.3.6b.previous: False
  • extensions.checkCompatibility.3.6p: False
  • extensions.checkCompatibility.3.6p.previous: False
  • extensions.checkCompatibility.3.6pre: False
  • extensions.checkCompatibility.3.6pre.previous: False
  • extensions.checkCompatibility.3.7a: False
  • extensions.checkCompatibility.3.7a.previous: False
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  • extensions.checkCompatibility.4.0.previous: False
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  • extensions.checkCompatibility.4.2: False
  • extensions.checkCompatibility.4.2.previous: False
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  • extensions.checkCompatibility.4.2a.previous: False
  • extensions.checkCompatibility.4.2b: False
  • extensions.checkCompatibility.4.2b.previous: False
  • extensions.checkCompatibility.4.2p: False
  • extensions.checkCompatibility.4.2p.previous: False
  • extensions.checkCompatibility.4.2pre: False
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  • extensions.checkCompatibility.5.0.previous: False
  • extensions.checkCompatibility.5.0a: False
  • extensions.checkCompatibility.5.0a.previous: False
  • extensions.checkCompatibility.5.0b: False
  • extensions.checkCompatibility.5.0b.previous: False
  • extensions.checkCompatibility.5.0p: False
  • extensions.checkCompatibility.5.0p.previous: False
  • extensions.checkCompatibility.5.0pre: False
  • extensions.checkCompatibility.5.0pre.previous: False
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  • extensions.checkCompatibility.6.0.previous: False
  • extensions.checkCompatibility.6.0a: False
  • extensions.checkCompatibility.6.0a.previous: False
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  • extensions.checkCompatibility.7.0.previous: False
  • extensions.checkCompatibility.7.0a: False
  • extensions.checkCompatibility.7.0a.previous: False
  • extensions.checkCompatibility.8.0: False
  • extensions.checkCompatibility.8.0.previous: False
  • extensions.checkCompatibility.8.0a: False
  • extensions.checkCompatibility.8.0a.previous: False
  • extensions.checkCompatibility.9.0: False
  • extensions.checkCompatibility.9.0a: False
  • extensions.checkCompatibility.nightly: False
  • extensions.checkCompatibility.nightly.previous: False
  • extensions.checkCompatibility.previous: False
  • extensions.lastAppVersion: 20.0.1
  • gfx.direct3d.prefer_10_1: True
  • keyword.URL: http://search.yahoo.com/search?fr=mcafee&p=
  • network.cookie.prefsMigrated: True
  • places.database.lastMaintenance: 1366238400
  • places.history.expiration.transient_current_max_pages: 104858
  • places.last_vacuum: 1302311246
  • plugin.disable_full_page_plugin_for_types: application/pdf
  • privacy.clearOnShutdown.cache: False
  • privacy.clearOnShutdown.cookies: False
  • privacy.clearOnShutdown.formdata: False
  • privacy.clearOnShutdown.history: False
  • privacy.clearOnShutdown.sessions: False
  • privacy.donottrackheader.enabled: True
  • privacy.sanitize.migrateFx3Prefs: True
  • privacy.sanitize.sanitizeOnShutdown: True
  • security.OCSP.disable_button.managecrl: False
  • security.warn_viewing_mixed: False


  • User JS: No
  • Accessibility: No
  • Top 10 Contributor
  • Moderator
2042 solutions 8891 answers

hello, maybe one of your addons is interfering here - however when the issue can't be reproduced reliably then it might be quite difficult to troubleshoot it...

Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

  • Top 10 Contributor
2357 solutions 20872 answers

Inconsistent problems are hard. When extensions update, they sometimes open a new tab to inform you about changes. I wonder whether that is somehow failing halfway through the process?

Question owner

I do have quite a few addons, I wouldn't be surprised if one of them is opening a new tab unsuccessfully. Is there a way to stop addons from opening tabs after an update? I would imagine that would be built into the addon, meaning "no". Of course, I can't check which addon isn't updating unless it updates, and the next update for the addon could fix this bug entirely. Although, if I could downgrade my addons, I might be able to figure out which developer to contact.

Question owner

Another idea: I'll disable automatic updates for addons on my desktop for now. When my laptop next sees this bug, I'll backup the profile on the desktop, and update addons one by one. If I don't see this bug again in the next month, I'll call it fixed. (I see the bug every week or so, not really timing it.)

Chosen Solution

I haven't seen this bug in a while, I'm going to call it solved. My guess is it was an addon, and the developer caught on and fixed the bug in time for their latest version. I see that some of my addons haven't updated since I posted this bug report (some of them in the last year), so if I see the bug again, I'll just manually update addons on another machine until I can reproduce it. Then I'll tell the developer and post it here, if anyone's interested.