When I'm reading dense information, often I want to follow links in the text by having them "pop up" over the underlying page in a modal way -- i.e. so that you can't lose context so easily if you switch windows, etc. -- when the modal closes, I'm back to the page that invoked it.
Firefox, like all browsers, allows you to "open link in new window" or "open link in new tab". What I want at these times is "open link in popup", intentionally suppressing the ability to focus the underlying page.
I've tried looking for an add-in which does this, with no luck. Anyone have any suggestions on how I can implement a modal popup like this?