Rated 5 out of 5 stars

@Webnician wrote "As a suggestion, I wish the EXIF data could be displayed either directly in the contextual menu, in the sidebar, or in a single always-on-top window. Currently, for every image you want to inspect, you must open another "properties" window. It's the appropriate place for the info, but it has limitations -- as soon as you click the page, the properties window is hidden. Then again, perhaps Firefox could provide the option of floating, copying, and saving the "properties" window"

I like the fact that I can have multiple properties windows - if you get a gadget that adds stay on top option to any window (I use the one from ActualTools, its payware but it works) then you can compare the data in the two, three ... six windows- and that's really useful. So I for one would like things to stay the way they are - ie the window persists until I tell it to go away. If you want it in the sidebar you can easily copy and paste it into something like Quicknote that can dock in a sidebar.

This review is for a previous version of the add-on (0.3.1).