Lubuntu 18.10 How to activate tap to click

this works for me
https://wiki.archlinux.org/index.php/Libinput#Touchpad_configuration

create:

/etc/X11/xorg.conf.d/30-touchpad.conf  

content:

Section "InputClass"   
  Identifier "touchpad"  
  Driver "libinput"  
  MatchIsTouchpad "on"  
  Option "Tapping" "on"  
EndSection

and finally

reboot

Activating tap-to-click with xinput via command line

1. Find your device id (in my case 13 bellow ):

   # xinput list
   

   Look for:

   ↳ ETPS/2 Elantech Touchpad   id=13   [slave  pointer  (2)]
   

2. Find the "Tapping" desired option code (in my case 283 bellow):

   # xinput list-props 13
   

   Look for:

   libinput Tapping Enabled (283): 0
   

3. Activate it with "1" using:

   # xinput set-prop 13 283 1
   

4. List props once more to confirm:

   # xinput list-props 13
   

   Look for:

   libinput Tapping Enabled (283): 1
   

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