As of about August my font drop down no longer shows the font in the font name. It works fine in other programs. I have emailed lightburn and they have no idea., but I see that there are a few posts on here of the same thing, however NONE with a fix. Its super inconvenient. I have also asked on FB and no one has any helpful suggestions.
I went through all the settings I could find in Lightburn and could not duplicate your claim. In every window (3 of them I think) a graphic of the font style was displayed.
I am also on an ACER notebook running Win10. Sorry I could not be more help!