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Lei Mao

Machine Learning, Artificial Intelligence, Computer Science.

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When I started to use a 4K monitor, I found Ubuntu 18.04 LTS does not support 4K resolution very well and has a lot of weird bug for it. One extremely common bug is that the dock at the left side of the screen, which someone may also call it launcher or sidebar, will be gone after returning from a screen lock. All the window layouts will be a mess then. I would have to reboot the computer in order to bring the dock back, which is very undesirable. It turns out that this is a known bug for Ubuntu but it seems that there is no one going to fix it. In this short blog post, I am going to talk about how to work around the problem temporarily.


The workaround is to reboot the Gnome shell by following the protocols presented below.

  1. Press ALT + F2.
  2. In the pop-up terminal, type r and press Enter.

The Gnome shell will restart without breaking the existing processes.

This is not a perfect solution since next time the problem might still happen when login back from a screen lock. But at least this time we don’t have to kill our processes and reboot the computer.