It's clear.. But strange, because utf8 - it's standard de-facto. I tested on Windows - all is work..
Ok! But I don't understand how book filename from temp folder (for example "C:\Users\ROR\AppData\Local\Temp\calibre_xgziak\sr v-deaebc\fcache\f\fmt-Calibre_Library-f.fb2") is transformed in "Gierbiert. Diuna. Piervaia triloghiia - Frenk Gierbiert_15.fb2". Please, help me understand this. I don't know python or js. I tried to debug through VS and Firefox, but understood nothing.
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YES! Thank you!!
I will try this.