Preview always freezes (beachball) whenever I try to modify and save a .pdf. I've tried resetting the preferences for Preview (as per Preview hangs when opening any image or pdf) and have also tried resetting the PRAM and SMC.
Initially I noticed the problem when I was trying to add bookmarks and save the file, but I tested doing other modifications (highlighting, adding text, etc) and get the same result.
One weird thing I've noticed is that I first started getting this problem a few weeks ago but it was only intermittently happening. Sometimes it would allow me to modify the file and save it, other times it would freeze. But now it freezes every time I try to save the file.
And just for clarification, the file freezes once I go to save the file.