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Using Unity 12.04 I have a black bar, a few pixels wide, appearing below the panel. This over-writes the top of a window which is immediately below the panel.

Although this may seem a minor problem it is irritating as the bar flashes as it builds up over time and this is extremely irritating. It also doesn't fit the theme (Ambience) and looks bad.

If I reveal the launcher and then hide it again, the part of the line covered by the launcher disappears, but it will re-appear again slowly over the new few seconds.

This seems to apply to other interface functions such as a mouse click or the appearance of a tool-tip, though in those cases it affects the whole bar.

Is there any way of removing this behaviour ?.

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A screenshot would be helpful – atenz Aug 17 '12 at 7:51

Try downloading Unity 2D as this seems like a graphical glitch.

sudo apt-get install unity-2d

EDIT: Once installed log out and on the log in screen choose Unity or Ubuntu 2D.

share|improve this answer
Unity-2D is already installed. Are you asking me to re-install it. Maybe this behaviour is due to a misbehaving indicator application. I notice that if I run Firefox full-screen (F11) the indicator panel and black line keep coming and going as the mouse is moved. – Bill Oldroyd Aug 18 '12 at 6:50
Say for example I click on the Shutdown icon (top right), both the shadow and the black bar disappear. As I move the pointer down the menu, first the shadow appears and then the black bar. – Bill Oldroyd Aug 18 '12 at 11:33
I have just realised that this behaviour also occurs around the Dash display when in Desktop mode – Bill Oldroyd Sep 1 '12 at 21:58

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