Keyboard not working after update to 18.04

I updated my laptop to 18.04 from 17.10 . The keyboard inputs are recognized only in the login screen after booting. Keyboard also works fine if I switch into the terminal from the login screen. But when logged in no keystrokes are perceived.

Installing xserver-xorg-input solved my problem !

Expanding on the above for the inexperienced, it is possible to turn on the on-screen keyboard (accessibility menu) as it is likely that external USB keyboards will also not work. After that perhaps the command

sudo apt-get install xserver-xorg-input-all

will do it. You need to shutdown and reboot each time (closing the lid usually just puts it to sleep).

At time of login press Ctrl+Alt+F3.
Then input your username and password.
After that, input the command

sudo apt-get install xserver-xorg-input-all

Then input

startx 

And your problem will be solved.

For anyone who still has this issue, in my case it's that somehow "Slow Keys" was turned on in the accessibility menu (little person icon in the upper-right corner of the login screen).

Was driving me crazy!

ubuntu 18.04 go to setting -> Universal Access -> Typing Assist -> Slow key

turn off Slow key

Also I've just discovered the "capitalise" button on the on-screen keyboard doesn't work. You may need type your password into libre office and use the capitalise menu button then paste your password into the terminal.