Fix Force Quit (X Is Not Responding) Dialog Freezing GNOME Shell 3.34

Are you getting a "Application / game is not responding. You may choose to wait for a short while for it to continue or force the application to quit entirely" message when trying to run a game or an application that takes a long time to start on GNOME 3.34 with Xorg, this causing GNOME Shell to become unresponsive / freeze with some screen flickering on top? This article presents a very simple workaround for this issue.

I don't play games too often on my computer, but today I wanted to relax by playing CS:GO on my Ubuntu 19.10 Eoan Ermine desktop (with GNOME Shell 3.34). So I launched the game using Steam, and GNOME Shell froze.

I know there was a bug causing some games and other programs that take a long time to start (showing a "X is not responding" popup dialog) on GNOME 3.34 with Xorg to freeze GNOME Shell, but I thought it was fixed by now. Apparently (according to u/Newbit13 on Reddit), this was fixed in Fedora 31, but there are still Linux distributions using GNOME 3.34 in which this wasn't fixed, like Ubuntu 19.10 (Eoan Ermine).

(Edit: I posted this article on November 18, and on November 21 this issue was fixed in Ubuntu. I'm still leaving the article up in case you're encountering this issue in some other Linux distribution.)

Luckily there are a few workarounds to fix this. The easiest way to prevent GNOME Shell from freezing when launching an application or game that takes a long time to start is to install a GNOME Shell extension called Disable force-quit or wait button. This extension removes the "Application / game is not responding" (with Force Quit and Wait buttons) popup dialog from being displayed, fixing this issue for any Linux distribution using GNOME 3.34. Yes, that's all it takes to fix this.

To install this extension, follow the GNOME Shell browser integration instructions if you haven't already, then go to the Disable force-quit or wait button page on the GNOME Extensions website. Next, click the OFF switch to the right-hand side of the extension name to turn it ON and install the extension.

In some cases the extension installs properly but is disabled immediately after installation. Double check that the extension is enabled by refreshing its page and make sure that the switch is set to ON.

After installing this extension, the Force Quit dialog should no longer be shown, no matter how long it takes to start a program, and the game or application that you're trying to launch should open without freezing GNOME Shell, and with no screen flickering.

Another workaround (provided by user mooninite1 on GitLab) is to start the game or application and then immediately open the activities overview (using the Super key or hot-corner), which will stop the force close / wait dialog from crashing GNOME Shell.

You might also be interested in this article: Fix Can't Login After Logout With Gnome / GDM3 On Ubuntu