How to show custom previews for all fonts in 10.9 Font Book? For years, I've enjoyed the feature in OS X Font Book where you can type in custom text and scroll through all the fonts to preview it.  Now on Mavericks, when I try to do this, it only works for single-font families.  All font families containing multiple fonts (e.g. bold, italic, etc.) will only show the default sample text.  How can I change this behavior to be like older OS X versions, where you can see the custom text for all fonts?  I'm hoping there's a plist somewhere that can be edited.
This works (at least in Yosemite Public Beta 2):

Open Font Book, select "Custom" from the View menu, double-click in the preview area and type what you want. Then, close Font Book. Then, re-open Font Book. Now, whatever you had previously typed should be the preview text for every font.

Annoying, yes, but it's a lot better than nothing!