Works great. Enables you to save a portion (or the visible region) of a webpage to SVG. Renders the visible elements into SVG fairly accurately. Obviously, since it has to convert what Gecko renders to an equivalent in SVG, it is not always 100% match (e.g. shadows are problematic, CSS blur does not work at all). But that is understandable, the capabilities of CSS and those of SVG are not 1:1, each can do a bit different things visually and matching them 1:1 is probably pretty hard, I can imagine.
BTW, the text parts of the page are kept as text so the screenshots can be manupulated, e.g., in Inkscape as needed. So good job, Mr. Becker; compared to what I've seen and tested in this category of add-ons, this is the best one I found by far.

Deine Addon, ist die BEEESSSSEER Herr Becker
I`m worried about the permissions :c