In the default Gnome desktop when you trying to open an application, the app window sometimes does not get into focus immediately, instead it pops up ‘xxx’ is ready notification and opens the window behind the current focused window.
This usually happens when another window is getting focused during the process of launching a desired application.
To get rid of the ‘Window is ready’ notification and focus window immediately, I think a quick enough system response should fix the problem. Besides, you can install “Focus my window” Gnome extension.
1.) Open terminal (Ctrl+Alt+T) and run command to install chrome-gnome-shell package if you don’t have it.
sudo apt install chrome-gnome-shell
2.) Then go to the extension web page in your browser. Turn on the toggle icon and install it.
Though the extension supports for Gnome up to v3.18, it still works in Ubuntu 20.04 and Ubuntu 20.10.
Don’t see the toggle icon? Click the link “Click here to install browser extension” and finally refresh the page.
That’s it. Enjoy!
(Optional) If you want to remove the gnome shell extensions, either turn off the toggle icon in the web page, or use Extensions (install the gnome-shell-extension-prefs package) utility.