LibreOffice does not have “script” font and I need such font on my LibreWriter.
Your question has nothing to do with LibreOffice because LibreOffice simply picks fonts installed system-wide, see robbleyd’s answer.
Install the font on your operating system by whatever means it uses. Then close and restart LibreOffice and it should pick up the new font(s).
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and if Libre Office does NOT pick up the new fonts?
Here’s what LIbreOffice 6.1 sees of my 100+ fonts: 8 or so fonts total.
permission problem! fonts will show up in LibreWriter if permissions on the newly created folders are changed:
# change permissions:
chmod -R ugo+rx /usr/share/fonts/
# now run this:
# build font information cache files
fc-cache -f /usr/share/fonts/
checkout my tutorial here: » Fedora CentOS RedHat – adding new fonts to the system for LibreOffice to use | dwaves.de