How are some people editing templates with the Visual Editor (VE)?

I mean, I switch to the VE on my preferences, and I still don't get the option.

I click to edit, it sends me to the source mode of the VE, and there, the option to switch to the visual mode is disabled.

I tried on both desktop and mobile device, and couldn't do it.

How do you think THESE PEOPLES are using the visual editor to edit templates? (I don't think they copy/pasting the URL parameter. Who would do that?)

I'm asking that because I'd like to find a way to prevent these sorts of edits, because they usually have side effect unintentional changes to the rest of the code.

EDIT - Extra detail for those who might not know.

We can spot when an edit was made with the visual editor because it usually come with a tag. On Kingdom Wiki it's VE.