So, you are here because you just installed Mac OS X Yosemite and you use Adobe Illustrator 5 and you can’t see the font preview in the type drop-down menu, right? What happens is when you mouse over a font, it will show the preview, but, it will show everything else as blanks. Frustrating! I went through every fix that was given on the Adobe site, including turning off font preview (why wouldn’t you want to see what your fonts look like?), turning on and off the dark menu, killing Illustrator preferences, etc. Nothing worked! Finally, I noticed this nugget on a back corner of the web and low and behold, it solved it!
Here’s what you do:
Open the Mac OS X System Preferences and search for ‘Accessibility.’ Once you are in there, select ‘Display’ from the left-hand list and then check the checkbox that says “Reduce transparency.”
If all goes well, you can now see all of your fonts in Adobe Illustrator CS 5 once again.
(H/T Capital Mac Service)