The above change restores the old behavior of locking up the image, so it should be reverted. An additional comment explaininng why aBlock must not be evaluated inside the argument of #accessDictionaryOfPreferencesIn: would be helpful.
Ahh, because aBlock might have a non-local return in it, leaving the Mutex unsignaled (and critical unenterable), is that right?
Took me a minute to see that problem.
Okay, I'll revert that method if no one else does by my next commit..
It would be even better to finally get rid of DictionaryOfPreferences.
Levente