When a field label is clicked, the focus seems to get set to the field’s first <input> element by default.
The behavior becomes problematic when dealing with radio list fields, because it messes with the user’s selection by changing it to the first radio input.
As a temporary fix, I added a hidden text input field right before every radio list and assigned the proper field ID to it. It now acts as a kind of honeypot for the default behavior. But I’m not sure if it is going to cause other issues.
By the way: In only found out about this, because I’m using the field labels to click-toggle the visibility of the field description (hidden on load, visible on label click). But I guess, even without that, accidental changes will occur from time to time.