Recently I got Safari hanging up when I try to pop up contextual menu in Safari.
So I sampled with Activity monitor.app when Safari got hang.
1724 TContextualMenuPlugin::LoadCMPluginsFromCFPlugin(FSRef const&, __CFArray*)
I found a suspect.
~/Library/Contextual Menu Items/DropboxPlugin.plugin
After removing DropboxPlugin.plugin, Safari's contextual menu is popped up as smoothly as ever.
However, every time Dropbox.app is started, it places the plugin. As I'm a programmer I can't bear torment of removing the plugin every boot time of Mac by hand. So I renamed the plugin:
$ mv /Applications/Dropbox.app/Contents/Resources/DropboxPlugin.plugin \
I'v used Dropbox for most half a year. Until this problem happened, it works great. I couldn't remind when I upgraded Dropbox app recently, so I suppose other changes of mac caused this problem.
Mac OS X 10.5.7
Safari 3.2.3 (5525.28.3)
Dropbox.app 0.6.402 or 0.6.507