Created attachment 461772 [details] [diff] [review] WIP v1 This bug might touch a line or two of toolkit/, but it almost exclusively involves modifying code in browser/ to get tab-modal prompts up and running in Firefox. I'll change the dependency on bug 562258 to bug 59314, once stuff gets duped over. This depends on bug 130078, since we would really like to be able to draw the tab-modal prompt over the content window, rather than having to hide the content window.
Created attachment 461773 [details] [diff] [review] modded version of bug 562258's patch v.2 to apply before applying the WIP patch
Now that bug 130078 has landed, I'll see what I can do with the overlay.
Rolling this into the main tab-modal patch.