https://extensions.gnome.org/extension/1336/run-or-raise/

Backup your shortcuts.conf when upgrading, since GNOME will wipe it. (Since the new version, shortcuts.conf will be saved in ~/.config/run-or-raise/ safely.) (This notice will be removed after Ubuntu 20.04 LTS release.)

I assume the run-or-raise style as the most efficient way of launching window. No more searching for your favourite program in a long menu, no more clicking on the icons. If the program already runs it'll get focus, else we launch it. Several years ago, OS creators finally realized that efficiency and let the users run-or-raise programs on the taskbar or dock by <Super>+number shortcuts. But what if you use more programs than nine? What if you don't want the unnecessary taskbar to occupy precious place on your screen?
With the emergence of Wayland over X.org in Ubuntu 17.10, we can't reliably use good old xbindkeys and jumpapp to master shortcuts. Here is a gnome-shell extension that let you migrate your favourite shortcuts to shortcuts.conf file.

• through GNOME3 extensions (official, easy, not always up to date)

OR

• put this dir to /home/$USER/.local/share/gnome-shell/extensions
• enable in gnome-shell-extension-prefs panel
• in the extension preferences, you may edit shortcuts.conf file to use your own shortcuts
• you may load new shortcuts without restarting, just change the file shortcuts.conf, and disable and enable.

On the first run, shortcuts.conf gets created from shortcuts.default if not exists. There you define your own shortcuts. The shortcuts may be defined in two ways:

This form let you cycle between open instances of the application or if not found, launches a new instance.

Run-or-raise form: shortcut,command,[wm_class],[title]

• wm_class and title are optional and case sensitive
• if none is set, lowercased launch-command is compared with lowercased windows wm_classes and titles

This line cycles any firefox window (matched by "firefox" in the window title) OR if not found, launches a new firefox instance:

<Super>f,firefox,,

This line cycles any open gnome-terminal OR if not found, launches a new one.

<Super>r,gnome-terminal,,

If you want to be sure that your browser won't be focused when you're on the page having "gnome-terminal" in the title, you may want to match running application by wm_class = Gnome-terminal on Ubuntu 17.10 or by wm_class = gnome-terminal-server on Arch... just check yourself by Alt+F2/lg/Windows everytime wm_class is needed.

<Super>r,gnome-terminal,Gnome-terminal,

You may use regular expressions in title or wm_class. Just put the expression between slashes.
E.g. to jump to pidgin conversation window you may use this line (that mean any windows of wm_class Pidgin, not containing the title Buddy List)"

<Super>KP_1,pidgin,Pidgin,/^((?!Buddy List).)*$/

To match Google-chrome and not Google-chrome-beta, help yourself with $ sign to mark the end of matched text.

<Super>KP_3,gtk-launch google-chrome.desktop,/Google-chrome$/,
<Super><Shift>KP_3,gtk-launch google-chrome-beta.desktop,Google-chrome-beta,

Another occasion you'd use regulars would be the case when you'd like to have multiple applications on single keystroke. In the following example, shortcut Super+Ctrl+(Numpad)4 focuses an IDE editor, either NetBeans or PyCharm. Because I'm mainly using NetBeans but for Python language I prefer PyCharm, I was wrong too often till I set single keystroke for both. (However, when no IDE is open, for launching NetBeans I use numpad and for PyCharm the 4 on the 4th row of keyboard.)

<Super><Ctrl>4,/opt/pycharm-community-2017.2.4/bin/pycharm.sh,,/(NetBeans IDE|PyCharm)/
<Super><Ctrl>KP_4,/opt/netbeans/bin/netbeans,,/(NetBeans IDE|PyCharm)/

Since it is very convenient to use a single file for all of your shortcuts (backup, migration to another system...), you can define standard shortcuts as well. These commands just get launched whenever the keys are hit.

Run only form: shortcut,command

This line will launch notify-send command.

<Super>h,notify-send Hello world

• For the examples, see shortcuts.default file.
• How to know wm_class? Alt+f2, lg, "windows" tab (at least on Ubuntu 17.10)
• You may change the configuration file on the fly. Just disable & enable the extension, shortcuts load again from scratch.
• In the case of segfault, check no conflicting keybind (are present)[CZ-NIC#1 (comment)], then submit an issue.