Making the Dock immutable A relative who has difficulty with mouse control keeps inadvertently removing items from his Dock.  I enabled Parental Controls to prevent him from doing so, but Parental Controls has a bug that prevents access to secure websites, including any banking site.

How do I lock the Dock so that it cannot be modified, without making use of Parental Controls?
I found an answer on Apple Support Communities:

defaults write com.apple.dock contents-immutable -bool true; killall Dock