With web content, we can right click and "Inspect Element" in the toolbox. It would be awesome if we had a similar thing for the browser toolbox. If there was no browser toolbox opened, it would open a new one and if there is one opened, it would reuse that instance and select the element. I'm partial to Shift+Right Click like the "Element Inspector" addon does with DOM Inspector, since that is very easy to open elements that don't usually have context menus associated with them. I'd be fine with this being an addon, but I'm assuming there would need to be some changes to the Browser Toolbox to support this behavior.

I'll consider this another vote for your identical bug from 4 months ago... ;) I'll try to think about a good way to do this soon.