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Sometimes an application gets in trouble with unity and then it won't be shown in the foreground anymore. To get to the application I have to minimize all other windows. Alt-tab doesn't bring the app to the foreground. This has happened with Firefox and Thunderbird.

Killing the app and restarting it doestn't help. It stays in the background after restarting it. Other symptoms:

  • The app doesn't have a menu bar anymore.

  • The white filled triangle transforms into a white arrow as shown below.

  • Only restarting the computer fixes the problem.

Because of the white arrow I think this might be a feature instead of a bug but I don't understand it. How can I undo this behaviour? I have spent about 4 hours googling it but there is not much to be found on unities triangles or applications that stay in the background.

enter image description here

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Some applications hang, as a result they preclude this behaviour. I found this exists in thunderbird and firefox.

I recommend using a little app called FlashFreeze.

enter image description here


FlashFreeze works in Ubuntu 11.04 and 11.10 and can be installed by adding the following PPA (Personal Package Archive) to your Software Sources: -


After adding the PPA run an update sudo apt-get update and install ‘flash freeze‘ from the Ubuntu Software Centre.

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Here is the official documentation for the open triangle:

Single open triangle: the application is running in a different workspace (by default, Ubuntu 12.04 sets up 4 workspaces).

Except that I have been also experiencing this and the application is under no workspace. Which is probably a bug, this one, or one of its numerous duplicates.

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