Hopefully there's not another thread about this for this particular issue, but the closest I found is the same problem on another version last year.
Anyway, whenever I try to change the font of a text style in Publisher 1.9.1, the program crashes on me. At first I thought it might just be when I try typing in the name to find the font quickly (gar to find garamond), but it's been happening to me just scrolling through the options to look for a font. I can individually change fonts outside of styles without the program crashing, so that'll have to be my workaround while the bug gets fixed so I don't get too behind. The program doesn't go unresponsive, just flat-out crashes and closes.