My bullet points show as the letter "a"

Hi there.

I am using LibreOffice Writer 5.1.3 on Linux Mint (Ubuntu).

Today, when I opened one of the documents I usually work with, I noticed that all of the bullet points show as the letter “a”.

I am sure that the error was caused when I updated from LibreOffice 5.0.6 to 5.1.3 , as downgrading back fixes the issue. I notice that opensymbol is part of the update.

Now, assigning other characters as the bullet point (like a check mark, or a box, etc.) works OK, it is just the original “circle” bullet point that is not working.

Interestingly enough, when I changed my original font to Arial, the bullet point still shows as the letter “a”, but all of the letters “a” in my document show as bullet points!

So it seems that somehow, LibreOffice is confusing the bullet point and the letter “a” as the same character.

Does anyone have any idea on why this happened and what can I do to fix it?

Thanks a lot in advance.