Including touchpad, touchscreen, dock, external screen, trackball. Mostly for my reference, but might be useful for others on same or similar laptops or OSes. Coming from Windows 10 + Chrome
Logitech Trackman Marble trackball. Left small button to be a middle click when clicked once, scroll modifier when held.
Right small button -> back button, Left small button -> middle-click. Run the following to create a shell script that sets the right settings, then add this to the "Startup Applications" in the desktop manager. (Could not reliably get this working using .xinitrc, .xprofile or xorg.conf but running the xinput settings after desktop login works reliably). Note - this doesn't work after disconnecting/reconnecting - might need to add a trigger to run this on a USB connect event.
cat <<EOT >> ~/startup_commands.sh
#!/bin/sh