Robert Pluim <rpluim@gmail.com> writes:

>>>>>> On Thu, 18 Jul 2019 11:03:10 +0200, Robert Alessi <alessi@robertalessi.net> said:
>
>     Robert> As of 2016, the latest versions of Unicode (as of 2016) have now
>     Robert> formally deprecated and removed the vowel+oxia combinations from the
>     Robert> Greek extended range, leaving only the vowel+tonos from the basic Greek
>     Robert> and Coptic range.
>
>     Robert> As a result of this deprecation, the sixteen characters found in
>     Robert> greek.el (Quail package for inputting Greek) that use extended
>     Robert> codepoints should be replaced with those that use basic codepoints.  All
>     Robert> affected characters can be found here:
>     --> 
>     Robert> https://wiki.digitalclassicist.org/Greek_Unicode_duplicated_vowels#Affected_characters
>
> I took a look at greek.el, that shouldn't be difficult.

Indeed, it's just a simple search+replace: