If you have added a structured application to the default ones provided by FrameMaker 8, proceed with caution before you install the patch for FrameMaker 8.0p266. The install will replace your applications definition file (structapps.fm) file without making a backup version.
I had customized my structapps.fm to include applications I created for a client. I tried to use one of those applications yesterday, but it wasn’t in my list of applications. Sure enough, those applications were gone from the definitions file. Sarah had the same thing happen to her definitions file, too.
Moral of the story: make a backup version of structapps.fm before you upgrade to version 8.0p266. (And I think Adobe should have known better than to do something like this.)