Mousepad edge scrolling disabled in Ubuntu 18.04

As you can see there is no option for enabling edge scrolling in Ubuntu 18.04. Now I can only scroll with two fingers, which it sucks.

How can I enable edge scrolling in Ubuntu 18.04?

It seems you didn't install whole packages, or packages are not up-to-date

install the following package:

apt update
apt install xserver-xorg-input-libinput

Or install and upgrade whole ubuntu packages this way

open a terminal and type

apt update
apt install ubuntu-desktop

if nothing happened generate new /etc/apt/sources.list from this link and repeat steps above

If still you have the problem mayble you need a full upgrade:

apt update
apt full-upgrade

after package steps you can enable it, this way:

Settings > Mouse & Touchpad > "Uncheck" Two finger scroll

Settings screenshot:

OR:

Settings > Devices > Mouse & Touchpad > Edge Scrolling

This is also accessible via DConf Editor as well. Go to org.gnome.settings-daemon.peripherals.touchpad and set:

 scroll-method: edge-scrolling

If using a unity session then you need to install xserver-xorg-input-synaptics package, ie. sudo apt install xserver-xorg-input-synaptics