Overt subject pronoun in Gothic vs null subject in Greek

The Gothic translation of the Bible is a word-for-word rendition of a lost Greek Vorlage (reconstructed by W. Streitberg in 1908Streitberg, W. (ed.). 1908. Die gotische Bibel. I. Der gotische Text und seine griechische Vorlage. Mit Einleitung, Lesarten und Quellennachweisen sowie den kleineren Denkmälern als Anhang. 2nd rev. edn 1919 (7th rev. edn with an addendum by P. Scardigli. 2000). Heidelberg: Winter.; 2nd revised edition in 1919). As previous studies have pointed out, one of the most interesting features of this version is the presence of the overt subject pronoun in instances where there is a null subject in Greek. Considering that Gothic is a null subject language, how is it possible to justify this feature? Based on a new collation that uses biblical textual witnesses not considered by Streitberg (i.e. Greek majuscule and minuscule manuscripts, Church Fathers, commentaries, lectionaries, and Vetus Latina manuscripts), this paper analyses the Gothic-Greek divergences involving the presence of the overt subject pronoun in the Gospel of John, in order to verify previous hypotheses and shed new light on this debated topic.