There are also three generally accepted versions of the OT, the official Masoretic Text, which has the least support in the NT with no clear citations, the Sead Sea Scrolls text, which is clearly cited in the NT in places in the gospels and the Septuagint which is the most cited with clear references in both Acts and Paul's writings.
But how does one decide which version to follow when the different texts record clearly different words? In Isaiah 19 for example there is a passage in which the DSS and the MT agree but the LXX differs noticeably. And even worse, Codex Sinaiticus, one of the earliest complete manuscripts, has a third version of the passage and the Isaiah Targum an Aramaic translation, has a fourth.
rewriter
You are woefully lacking in referring to the Dead Sea texts as a validation for versions of the Old Testament because modern Jews and Christians reject the cannon of the Essenes.
The non-canonical books most frequently found at Qumran were the Book of Jubilees and the Book of Enoch (1 Enoch). These apocalyptic texts were incredibly popular with the Essene community, surviving in multiple manuscript copies.
Other widely read non-canon writings at Qumran included:
The Book of Tobit: A deuterocanonical book found in six copies.
The Wisdom of Sirach (Ben Sira): Found in several Hebrew fragments.
Testaments of the Patriarchs: Including various copies and adaptations of the Testaments of the Twelve, such as the Testament of Levi.
Sectarian Qumran Writings: Original compositions unique to the settlement, such as the Community Rule, the War Scroll, and the Temple Scroll.
You quote Codex Sinaiticus as a source but The Codex Sinaiticus (c. 330–360 CE) is another nearly identical early manuscript. It holds the oldest surviving complete copy of the New Testament, along with roughly half of the Old Testament. Codex Sinaiticus conversely and uniquely includes books like the Epistle of Barnabas and The Shepherd of Hermas as sacred books.
A more complete listing of versions of the Hebrew Bible include:
The Septuagint (LXX): The earliest translation of the Hebrew Bible, rendered into ancient Greek in Alexandria, Egypt, between the 3rd and 2nd centuries BCE. It contains variations in text and order compared to the Masoretic Text and includes additional writings (often called the Apocrypha).
The Dead Sea Scrolls (DSS): Discovered in caves near Qumran between 1947 and 1956, these ancient scrolls date from the 3rd century BCE to the 1st century CE. They contain fragments of every book of the Hebrew Bible (except Esther) and provide vital evidence that multiple textual versions circulated concurrently in antiquity.
The Samaritan Pentateuch: An ancient Hebrew version of only the first five books of Moses (the Torah), preserved by the Samaritan community. It is written in a paleo-Hebrew script and features unique textual variants that emphasize the sanctity of Mount Gerizim.
The Targums: Aramaic translations and paraphrases of the Hebrew Bible that arose after the Babylonian exile when Aramaic became the common spoken language of Jewish communities.
The Peshitta: The standard Syriac translation of the Bible, created for the Aramaic-speaking Christian communities in the 2nd and 3rd centuries CE.
The Vulgate: A 4th-century CE Latin translation by Jerome, who translated the Old Testament directly from original Hebrew manuscripts, which became the standard text of the Catholic Church