John 5:16 (traditional text)
και δια τουτο εδιωκον τον IN [+οι ιουδαιοι]
και εζητουν αυτον αποκτειναι
οτι ταυτα εποιει εν σαββατω
and because of this they persecuted Jesus
and sought Him to murder (Him),
since these He did in the Sabbath...
A, N, X, Δ Θ ψ, f13, 213, 865, 1071, Byz, Maj (Majority of all continuous MSS),Latin: - e, f, q, r1, 27, Sy-P, Sy-H, Bohairic etc. Lect,
OMIT: P-66/75 א, B, C, D, L, W, 0141, f1, 69, 33, 397, 565, 579, 597, 821,
892, 1010, 1241, 2718, 2786, pc20,
Lat(a, aur, b, c, d, ff2, l, vg), Sy-S, Sy-C, sa, bopt
Here one can imagine a typical 3rd-4th century manuscript, with its contractions of Sacred Names and common words, such as Jesus, Christ, God, Jews, etc., allowing for shorter lines and compacted Uncial (capital) letters.
The result is another opportunity ripe for a Haplography error, and sure enough a clause was dropped at some point. That the Jews were seeking to kill Jesus is quite plausible, given the reason for the anger: public defiance of the Sabbath, in the very Temple of Jerusalem. And we need not limit this to the religious authorities, as Paul's experience in Acts demonstrates.
Not something a Jewish scribe would easily invent, but quite natural to leave omitted, for the purpose of toning down blanket accusations and racial hostilities.
The split among the Syriac versions shows both readings to be as old as the 2nd century.
The UBS text doesn't even note the variant. It becomes yet another completely undocumented alteration of the Traditional text, almost unanimously adopted by 'modern' versions simply because they follow UBS or Nestle/Aland by habit.