Capslock (and other keys) indicator for Ubuntu 18.04
Solution 1:
You may use one of the following GNOME shell extensions to achieve your goal.
Lock Keys
This extension shows Num lock or Caps lock (or both) status on the top bar.Keys Indicator
This extension shows Ctrl, Shift, Alt, Num lock, and Caps lock status on the top bar.Lock Keys (another one)
Numlock & Capslock status on the panel. Icons are auto hidden. Simplified with no menus, notifications or settings.
Solution 2:
There's a ppa for indicator-keylock on Ubuntu 18.04
sudo add-apt-repository ppa:tsbarnes/indicator-keylock
sudo apt-get update
sudo apt-get install indicator-keylock