Here the 1888 LDS edition omitted the subject pronoun ye. Since this edition never served as a copytext, no subsequent LDS edition has followed this shorter reading. Note here that the preceding imperative clause (“therefore come unto me”) has no ye. The lack of ye in the first clause may have prompted the 1888 loss of the ye in the second clause. Here is another passage where the ye is not repeated in every imperative clause:
Summary: Maintain the text in 3 Nephi 12:20 where ye occurs in the second imperative clause but not in the first one.