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What's causing this strange overlay?

  • 10 replies
  • 1 has this problem
  • 2 views
  • Last reply by Mike Hanson

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I'm using FF 26.0. Beginning yesterday, I'm seeing a strange circular ghost appear just to the right of the center of the FF window (http://boxsoft.net/images/firefox_ghost.png). When I resize the window, the image floats to the same position to the right of center (it move as the center moves), until the window is beyond a minimum width, at which point it locks to a fixed distance from the right border.

I've tried disabling all of my add-ons, which didn't help. If I restart FF it's gone, but I can get it to come back by restarting FF, going to FireFox / Help, then pressing Ctrl+W to close the help tab. The image appears on the remaining blank tab. (Closing the Help tab by clicking on the tab's X doesn't cause the image.)

For a while it seemed that pressing and holding the Ctrl key would turn it on and off (a second after pressing the key), but it's not behaving that way anymore.

Any thoughts?

Mike Hanson

I'm using FF 26.0. Beginning yesterday, I'm seeing a strange circular ghost appear just to the right of the center of the FF window ([http://boxsoft.net/images/firefox_ghost.png]). When I resize the window, the image floats to the same position to the right of center (it move as the center moves), until the window is beyond a minimum width, at which point it locks to a fixed distance from the right border. I've tried disabling all of my add-ons, which didn't help. If I restart FF it's gone, but I can get it to come back by restarting FF, going to FireFox / Help, then pressing Ctrl+W to close the help tab. The image appears on the remaining blank tab. (Closing the Help tab by clicking on the tab's X doesn't cause the image.) For a while it seemed that pressing and holding the Ctrl key would turn it on and off (a second after pressing the key), but it's not behaving that way anymore. Any thoughts? Mike Hanson

Modified by cor-el

All Replies (10)

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Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe Mode start window.
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I turned off hardware acceleration, and I haven't seen the image reappear. However, I can't possibly imagine how it would cause the behavior that I observed.

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This can't be caused by hardware acceleration.

Do you still gets this icon with all extensions disabled?

Did you try to uninstall Firebug in case this extension is causing it?

This is either caused by an extension as it doesn't look like the auto-scroll icon or you may have some malware.

  • Firefox/Tools > Options > Advanced > General: Browsing: "Use autoscrolling"
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Since turning off hardware acceleration, I have not seen the image, yet I cannot fathom why that would make any difference.

Yes, I had tried turning off Firebug before posting my message, although I did not actually uninstall it. Note that I didn't change my Firebug settings anytime recently, yet this just started appearing yesterday.

My auto-scrolling switch is (and was) turned ON. I've just turned it off, but I don't know what it will do.

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When auto-scrolling is enabled then you can middle-click with the mouse on a web page to get a special icon and you can scroll the page by moving the mouse up and down or left and right.

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Ah, OK. I've never used that feature, so I can definitely turn it off.

On my machine (running Windows 8.1), the middle button brings up all the task windows, so that I can change tasks. I don't use this either. ;)

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Sounds that you have mouse driver software that adds special features, so what you saw may be one of them.

Best is to leave at least the left and right and middle mouse buttons to their default actions and use extra mouse buttons if you have them to activate special features.

You can check that in the "Windows Control Panel > Mouse".

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Nope, it's a standard Microsoft Mouse (Wireless 5000), and all I've changed is to make the left custom button (by my thumb on the side) act as a Back button. Nothing special there.

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Maybe check for a stuck Control (ctrl) key and disable this feature, here in the mouse menu if its checked.

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Nope, it wasn't that. Thanks for weighing in.

BTW, the strange image still hasn't returned, since turning off hardware acceleration. I can only assume that something in that code triggers this unwanted behavior. If it returns I'll let you know.