回复：求助：关于firefox 的问题

Here is what is happening:
Bookmarks is a html file which is located at your profile folder. FF updates it whenever you close FF successfully (flush something in cache). If you computer crashes, FF fails to update bookmarks properly that causes the file system to trancate it on the next booting.

So, don't worry about FF, but you might need to keep an eye on why does your computer 死机?