I had a Compose Key set to right Super (a.k.a. Windows) key using Gnome keybindings. After upgrading, I seem to have lost the Compose Key function. Where can I enable Compose Key? I can't find any option under System Settings > Keyboard.
In Ubuntu 12.04 and before, go to
Keyboard Layout in
System Settings, then hit the
Options button on the lower right. You will see one called
Compose key position, where you can set it to Right Win (i.e. right Super).
In Ubuntu 16.04 and 14.04 go to
Keyboard within the
System Settings. Select the
Shortcuts tab, then
Typing from the list at left. Clicking to the right of the
Compose Key setting will bring up a menu of different options.
Note that the only options are Right Alt, Right Ctrl, Right Win, Left Alt, Menu, and Caps Lock. If you wish to set it to a key not listed, see this answer.
In Ubuntu 18.04, since Ubuntu has now adopted the GNOME Desktop, things are more complicated: there is no longer any way to set the compose key within the regular system settings.
You must first download an entirely separate program,
GNOME Tweaks. This can be found in Ubuntu Software, or can be downloaded with this command via a terminal:
sudo apt install gnome-tweak-tool
Once Tweaks is installed, run it. Then hit
Keyboard & Mouse on the left. In the
Keyboard section on the right, an option to enable the compose key can be found.
Note that there are still limited options for what key can be set: Scroll Lock, Right Alt, Caps Lock, PrtScn, Right Ctrl, Left Alt, Menu, and Right Super. If you wish to set it to a key not listed, the solution in this answer still works.
In Ubuntu 13.10
In Keyboard settings window, under Shortcuts -> Typing set Compose key to Right Alt (or other).
In Ubuntu 12.04 LTS:
Select System Settings... from system menu;
Under the tab labelled Typing click Layout Settings;
In keyboard layout window, click Options... button;
Finally in the Keyboard Layout Options window select Key(s) to change layout and mark the binding of your choice. (I use Shift + CapsLock to toggle the layout.)
Using compose key:
ëyou press Compose followed by " then e keys.
(..here you'd have to remember the two character combination)
Using hexadecimal Unicode character code point:
Press (and release) Shift+Ctrl+U, then, while underlined u is displayed, enter the hexadecimal Unicode character code point followed by Return or Space.
e.g. Ctrl+Shift+u followed by 2 6 3 b and then Return or Space for ☻ .
(..so this one would require you to remember the Unicode number)
In order to set up the Compose key you must go to (setting -> keyboard -> layout settings -> keyboard settings -> then go to the typing tab -> press and hold the Compose Key setting -> move you mouse down to select the key you want to assign Compose to.