What app or function caused this?
The equivalent of ‘S’ in Greek is written/typed in two ways: σ & ς
ς is always used at the end of a word; σ anywhere else.
I had a large amount of Greek audio and text transcript. I broke up the text into phrases (where the audio paused). I used TextEdit to replace all spaces with underscore, and then used the phrases for markers in Amadeus. Finally, I had Amadeus “split according to markers” to create audio files for Anki to play.
Anki’s “media check” utility gave a long list of missing files and a long list of unused files. But many items seemed to be on both lists! After fussing with it for a while, I finally realized that every time ς was not followed by a letter, but by an underscore or a .mp3, it had been changed to σ.
What would have done this? (It was definitely not a replacement I did anything to induce.)
Another possible culprit was using tr "[:upper:]" "[:lower:]" to remove capital letters from the file names. But ς is not upper case, so should not have been changed.
Finding it was further complicated by a gratuitous change of composed characters to the decomposed equivalent that also happened in the process.