It is easy:
1. Step: Create a folder with Windows Explorer
2. Step: Create library
3. Step:Libraries are ready
4. Step: Import book and rename author and/or title
After clicking 3 or 4 at error messages, the change is accepted but the old versions are not deleted.
I use in this demo as first letter
⴮reserved
፡ ፡ETHIOPIC WORDSPACE
�� 𒍮CUNEIFORM SIGN ZUM
@BetterRead: No, I don't use a plug-in 'GetFileName'. I deleted all user-installed plug-ins and a lot of the other. Did not help.
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I hope the method of how I inserted the screenshots works. Otherwise, please tell me how to do it.