Ubuntu 14.04 was indeed installed from the factory, but the problem arose after upgrading the OS according to normal procedure, having installed no third party software. I have, however, managed to solve the problem myself. I posted the solution below for anyone who may have the same problem as me. Notes for beginners:  Easy step-by-step solution: There should be a file named "70-synaptics.conf" in "/usr/share/X11/xorg.conf.d/". To check, type the following in the terminal:  If "70-synaptics.conf" is present, it should appear within the list. If it doesn't, check for "50-synaptics.conf" or something similar and proceed replacing all mentions with that file. However, you should not edit that file as the changes you made to it will be overwritten next time you upgrade.  Instead, copy and paste the file to "/etc/X11/xorg.conf.d/"  Open the file with your text editor:  Add the following lines to the file:   You can also add other options. The full list can be viewed by typing "synclient" in the terminal.  The ones added here are:   I also added a couple of other options, decribed below:  Additionally, you should also try adding and changing the values of the two options below if palm detection remains wonky (shown below with their default values):   
After upgrading to the non-supported Ubuntu 17.10, the touchpad configuration is messed up. Side scrolling doesn't work anymore and something about either the palm detection is completely off so that the text cursor randomly jumps when I type. This same problem happened again after a complete reset. Is there a way I can load the original touchpad driver/configuration that was for the supported Ubuntu 14.04?
XPS 13 9350, Ubuntu 17.10, touchpad issues