You can effectively turn off the Unity launcher through several steps.
- Make the launcher autohide.
- Prevent the mouse cursor from triggering the launcher when the mouse moves left.
- Disable the Super key from triggering the launcher.
Autohide the launcher
You can try CCSM to autohide the launcher.
To do that, install CCSM by clicking the link. After installing it, open CCSM and go to 'Ubuntu Unity Plugin' under Desktop.
Choose 'Autohide' option in the dropdown list next to 'Hide Launcher'. Now, the launcher will show if you move your cursor to the left side or you press the Meta key.
Prevent the mouse cursor from activating the launcher
So, in order to prevent the launcher from appearing when you move your cursor to the left side, go to 'Reveal mode' in the same option page and unselect all the selected corners. If your dialog box looks like the picture below, your launcher won't appear even if you move your mouse to the left side.
Disable the Super key from triggering the launcher
Change the shortcut for Key to show the launcher to none.
These three changes will effectively turn off the launcher.
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