Still, this would not be something that webtrees would have added unless you entered it as a fact (without fact data). What does the source XREF point to, this may give you a hint as to what you were trying to enter!
The TYPE tag would have been something you tried to enter, maybe as a copy and paste. I can’t recall any function in webtrees that generates an EVEN tag automatically!
First of all: I don't remember I created this source manually
The mentioned source object is a deed, the birth registration. The details of the deed tells me the year, the municipality, the document number and the register type.
While you are sure webtrees doesn't create this line, I have to figure out how these lines arised.