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Why is there a little white Window in the left upper corner?

  • 2 replies
  • 1 has this problem
  • 4 views
  • Last reply by Wayne Mery

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appears in WIN7 and Win10 Thunderbird Daily 64. Closing with alt+F4 But it comes again if I get messages

appears in WIN7 and Win10 Thunderbird Daily 64. Closing with alt+F4 But it comes again if I get messages

Chosen solution

If you have issues with a daily developer build I suggest you file a bug so developers can fix it before release. https://bugzilla.mozilla.org/

Note there is no dedicated Thunderbird 64, if you have one is is not even as far forward as being in a beta channel. Where did you get it?

Before filing bugs it is important to be sure the issue is not an add-on or other software so I suggest you follow the following path. To diagnose problems with Thunderbird, try one of the following:

  • Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
  • Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, OSX
If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.
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Chosen Solution

If you have issues with a daily developer build I suggest you file a bug so developers can fix it before release. https://bugzilla.mozilla.org/

Note there is no dedicated Thunderbird 64, if you have one is is not even as far forward as being in a beta channel. Where did you get it?

Before filing bugs it is important to be sure the issue is not an add-on or other software so I suggest you follow the following path. To diagnose problems with Thunderbird, try one of the following:

  • Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
  • Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, OSX
If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.
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