Many of you are not DBAs or developers. You spend most of your time browsing tables, running queries, and answering questions that help make your business ‘go.’
The SQL Developer Connection Tree shows a whole lot of stuff that you might not ever use.
So turn it off.
Tools – Preferences – Database – Navigation Filter
By the way, this a new feature for version 4.0, so if you don’t see it, it’s time to upgrade.