Just me stopping for a moment to express a simple desire…(ahem o’ Apple!)… If you have a multi-monitor setup (I have two: my Mac itself, and another to its left), moving my mouse around a certain part of the screen (no clicking), causes the dock to move from one monitor to the other.
Some people may like this. I do not. I really just want my dock to stay put on the right hand screen.
If Apple would just add an option in the Dock preferences to lock the dock the the current screen that would be awesome. It could be deselected as a default so that everyone who thinks the dock works fine would be happy, and people like me could make sure that the dock was on the screen we want, and check that option and no longer have it popping around now and then from screen to screen.