at first this plugin didn’t woork, then i disabled all the other plugins and it worked. then i changed some new fonts, the plugin stopped working again. seems it was not beacuse of other plugins and the 3party theme. is that something to do with the cache thing? by the way im using some chinese fonts.
In your case here though you have assigned the font to blockquote actually there is another element inside it and it is taking the apple font. So please keep this in your custom element box and assign font to it.