If you go to the settings/graphics and change some values of the drop down box - if you choose to not select a value from the drop down box, your character moves to your mouse. This seems to happen with any of the drop downs.
In the imgur linked, I go to change the grass density. Instead, I click on the bar that originally opened the drop down and my character moved toward my mouse.
Consistency
Very repeatable.
My expectation of what should happen
If I click anywhere in the settings menu, my character should not move. This statement is true when the drop down is not open. However, when a drop down is open and I click somewhere, my character moves there.
PC Details
Windows 10
Maximized Window Mode
Game opened through Steam