Starting a few hours ago every external link I press in say my email client, the IM windows I have open, etc open a new window but the pages never open - just the blank window.

I checked my settings, it was nothing in them and it's always been set to open new links in a new tab, anyways. I hadn't been fiddling with anything before this started happening. I'd been away from the keyboard, actually.

I really need to know whats going wrong, please?