Pinging our hyph.patterns wizard @cramoisi to confirm it is fine to go from не8 to не1 (and not to не7 or не9) to allow such hyphenation (while, I guess, still avoiding any other more precise pattern like не4не if we don't want to hyphenate нененене).
(I guess we both can't read Russian and would pronounce that héhéhéhé :) )

Well, "не-не" is also an acceptable hyphenation. :) I made it with lowest priority so it could be overridden by more specific rules.

It reads "ne" :)

Hi :-) @poire-z Odd numbers are there to allow hyphenation. Even numbers to forbid it. So going form 8 (higher non hyphen priority) to 1 ( lowest hyphen priority) is perfect for it won't conflict with other rules.

This is a common sense typographical rule. "Не" is a negative prefix or particle, so separating it makes the text easy to be misread:

Недопустимы неблагозвучные переносы, а также переносы, ведущие к двусмысленному прочтению текста, способные запутать читателя, привести к недоразумениям, нарушить нормальный процесс чтения. Например, нельзя отделять отрицание «не» от следующего слова или переносить конечный слог «не» какого-либо слова в другую строку, если далее следует глагол
https://print-standart.ru/printing-reference/174-technical-rules-of-typing
https://www.nrap.ru/pub10_90_1_1054.html

I suggest reverting this change.

@Abradoks, thanks for the reference, it looks I didn't research this thorough enough. I'll revert this change.

And anyway, there's also algorithmic hyphenation as an alternative, it works pretty well for Russian.