aqwsed12345 : It is worth considering one of the new readings of Nestle-Aland's latest 28th edition
I agree you have put the textual problem of Jude 5 clearly, but it was not a new reading. The first edition of the UBS Greek New Testament contained the reading "Jesus" in the text, but this was changed in the third edition when it was replaced with "Lord" in the text and "Jesus" in the margin. Now in NA28 they have returned "Jesus" to the text.
In his Textual Commentary on the Greek New Testament, Bruce Metzger explains why "Lord" was preferred. He says the majority of the Committee was of the opinion that the reading was difficult to the point of impossibility and explained its origin in terms of transcriptional oversight (as the nomen sacrum for "lord" (ΚΣ) can be mistaken for the nomen sacrum for "Jesus" (ΙΣ)). They observed that nowhere else does Jude employ the name "Jesus" alone and others have queried whether Jude would refer to "Jesus" as "saving Israel out of Egypt" at a time when he was not known by that name.
Verse 5 has a number of variations :
I desire to remind YOU, despite YOUR knowing all things once for all time, that [ ΚΣ (Lord) / OΚΣ (the Lord) / ΙΣ (Jesus) / ΘΣ (God) / ΘΣΧΣ (God Christ) ], although he saved a people out of the land of Egypt, afterwards destroyed those not showing faith.
with the following manuscript support :
Lord [ΚΣ] ... codex Sinaiticus (4th century), codex Athous Lavrensis (8th/9th century)
the Lord [OΚΣ] ... codex Ephraemi Rescriptus (5th century), Syriac (7th century), codex Cyprius (9th century), codex Regius (13th century)
Jesus [ΙΣ] ... codex Alexandrinus (5th century), Vaticanus (4th century), minuscule 33 (9th century), miniscule 1739 (tenth century), miniscule 1881, Origen, Cyril, Jerome, Coptic
God [ΘΣ]... codex Ephraemi Rescriptus (2nd corrector), some Vulgate mss
God [the] Christ [ΘΣΧΣ] ... papyrus 72 (3rd/4th century)
All these variations suggest there was some confusion about the text, and the fact that "Lord" has no definite article in some manuscripts suggests it replaced a name. The original might have contained the name "Jesus" which many manuscripts support despite it being unlikely, but others have suggested that this textual confusion occurred because Jude originally used God's name in some form which is why NWT includes "Jehovah" in this verse.