When I use Arabic characters with "Typewriter" & "Inline Note" annotations, they will not appearing at all.
These 2 types of annotations should support Arabic characters
Linux: Fedora 32 X64 bit Cinnamon edition.
KDE Frameworks Version: 5.70.0
Qt Version: 5.14.2
Other type of annotations, namely "Pop-up Note" already support Arabic characters okay.
*** This bug has been marked as a duplicate of bug 305534 ***