When I select a File display font that doesn't support non-Latin characters (e.g. Centaur) and you have them in filenames, either the characters will be missing or be replaced by various placeholders like boxes and crosses depending on the font. This is true of Cyrillic, Korean, Greek, Unicode glyphs (), and many more.
I'm guessing this entirely normal and expected behaviour, and easily "fixed" by choosing a better font that supports these characters, such as Segoe UI. It doesn't affect anything, just the display - the filenames are unchanged.
However, if I use the same font in thumbnail mode, suddenly these non-Latin characters are shown correctly in filenames again - with the Latin characters in my selected font, even if it doesn't support these characters at all.
Wah?? How does this even work? Is it being handled by some Explorer feature wrapped through DOpus?
And, maybe, is it something we could have in ordinary Detail and List listers?
Are you sure you don't have a different font selected for Thumbnail mode?
Yes, sure. I've confirmed it with a selection of fonts in Thumbnail and Lister. Have a look at an example I prepared using Centaur set as both File display font and Thumbnail labels font:
They are neither the same font face nor the same font size.
Sorry. For some reason I hadn't saved the change. It is definitely the same font now.
It's not just this font. Are you getting the same thing?
I should also point out that the font for the Greek and Russian characters here is different, because Centaur doesn't have these in its character set. Therefore the characters are taken from elsewhere. Where? Dunno. Why only thumbnails? Dunno.
Other fonts may not show glyphs, or Korean, depending on what they natively have. Most Windows10-bundled fonts, and some Google fonts, have the full set.
The technology is called font linking, and it's something that Windows does (or is supposed to do) automatically. I'm not sure off-hand why it would only work in thumbnails mode - possibly something about how we render the text in the other modes switches font linking off. It's not something we're doing deliberately though (I don't think you even can switch it off deliberately).
Ah, thanks for explaining.
It's no problem for me to use a different, more supported font for listers. I just thought I was going nuts
Thank you for investigating this bit of weirdness.