Blocks per user setting/individual I am having my navigation links in my utility bar which is in a block named 'tray'; however, some users prefer to have the navigation links in the normal position and that is in a side panel inside a block named 'second sidebar'.

How can I make it so that the users can choose on their profile to either use the utility bar and navigate from there, or leave it as it is and have the links in the sidepanel.

Update: I mentioned panels, but it should have been blocks.
You can add per user preference settings. Check this for a working example of how to add a preference setting in the user profile form and how to store and read it.