I want to suggest a feature for the filter.
There should be an option in settings if the filter should look for matching diacritics or not.
Instead of placing this option in settings it would even be better to make it more reachable in the near of the filter-field, because someone probably wants to switch it on or off during work.
I try to keep the tags and filenames of music-files according to the orginal way of spelling. Therefore I have a lot of diacritics in tags and filenames of different languages. But trying this does not mean that all my tags are this way and that there are no different spellings present. The desired feature would make it easy to look for those that are in different spelling and not oversee them. And to be honest: I myself often do not know if I used the original diacritic or not.
Examples for diacritics:
and so on
In all these cases the filter should alternatively be able to list all macthing files wether they are written with a corresponding "normal" character (Renne, Farina, Noel, Francoise ...) or one of these diacritics or not.
At the moment I help myself with the very
recommendable third party software "Everything"
This software has the suggested feature in it's options.
But as this software only cares about filenames i cannot filter for tags and anyway it would be a good feature for MP3Tag too.