Nice extension. I prefer to view page source in a side panel and this is the only way I have found to do so. Firebug won't; AOIS won't and so on.
However, I gave it only 3 stars because there is no way to close the panel once it is opened. There is no close button on the side panel, no close option in the context menu; clicking on the page source button again just opens a window. I had to restart Firefox to get rid of the side panel. This won't do.
I like this extension but surely, it couldn't have been too much trouble to add a close option.
the idea is great, but it has two big bugs: - when submit a form and take me to another page, the extension shows the form's page source instead the submited page - when changing preferences to view source in another tab, it opens thousands of blank tabs