Return HUD key from Mod 2 + Alt L back to Alt L

I was fooling around in the keyboard shortcut section, and accidentally changed the HUD's shortcut from Alt L to Mod 2 + Alt L.

Now, whenever I hold and even press the alt key, HUD will pop up. I don't have the option to hold the alt key, and then press F4 to close a window.

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How can I get this back to normal? Every time I try too, I can never get the shortcut back to just Alt L.

Solution 1:

Due to a bug described here:

https://bugs.launchpad.net/ubuntu/+source/unity/+bug/981628

you can't change HUD key from mod2+ ALt L back to Alt L.

The solution is quite simple, just turn NumLock off and try again.

You'll find the default setting is back again!

You can use CompizConfig Settings Manager to change the key used to show the Unity HUD.

To open terminal hit Alt+Ctrl+T and run following command:

sudo apt-get install compizconfig-settings-manager

Or search for 'compizconfig-settings-manager' and install it from there.

Once installed, Hit Super key (Windows key) to open Unity dash and search for "ccsm" and open it.

In CompizConfig Settings Manager Navigate to Desktop > Ubuntu Unity Plugin

Under the Behavior tab click on little cross in front of "Key to show the HUD", This will set the key to default (Alt)

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