Firefox and Google Chrome tend to load pages indefinitely or stop loading them altogether unless I turn Safari on, or to be more precise, open a new page in Safari each time this happens. This is very odd and hasn't started doing this until a couple months ago. I have tried everything from completely wiping both browsers off completely via a clean install and checking corrupted font to restoring the system from scratch using the disk utility and reinstalling Flash/Java. This happens no matter what OS I use. I am currently using Mountain Lion on a late 2009 Macbook Pro.