
a) Install Minbar Prayer Times from Ubuntu Software Center
b) Include minbar in startup program
c) Set the preference of minbar to "startup minimised to tray"
In older Ubuntu versions Minbar Prayer Times should be located on right top panel, but now it is missing. Rebooting the machine did not help.
Then I did the following steps to show the Minbar icon:
Step 1: From Ubuntu terminal (Ctrl+Alt+T), enter the command
sudo apt-add-repository ppa:gurqn/systray-trusty
Step 2: enter the command
sudo apt-get update
Step 3: enter the command
sudo apt-get upgrade
Step 4: then reboot the system by entering the command
sudo reboot
Finally the icon Minbar Prayer Time shown on top panel, and it starts (but minimised mode) every time the system starts.
Another reference related this problem can be found here.