The process to create the .pot file (the index to later on update the .po files) is looking into the .py and into the .xml file for translatable strings, collect them all to generate the .pot file.
From what I understand the py that WanWizard point to is loading a standard python library.
https://iso639-3.sil..._Name_Index.tab
ell Modern Greek (1453-) Greek, Modern (1453-)
So those are not part of the Enigma2 translation process.
But I think that the if the other strings are translated if it is probably because the same term is already used somewhere else, so the translation is already included into the .pot/.po files and so they are translated.
So I guess that nowhere else the term: Modern Greek (1453-) is used in OpenPLi, so this one is not translated.
You should not add extra strings into the translation you submit because they will always be overwritten during the po files update process. Those extra strings are deleted since not found in the source.
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