XML : Getting the Notepad++ XML parsing error "Extra content at the end of the document" even though there is none

I am getting the abovementioned error message when trying to validate my 55 mb XML file in Notepad++. The first enocountered error is here (line 1441520 out of 22258651): Screenshot from Notepad++

I have turned on Show all characters. Nothing suggests that there should be any illegal characters at the end of the line. As you can see on the screenshot there are no other hidden characters than CR+LF.