Congratulations on all the great work that's going on with the offset stuff. It's a very useful feature!

However...

Currently, an Inkscape SVG document using SPOffsets will not render properly in other conformant SVG user agents. This is not good.

To remedy this:

1. use our own inkscape:href (or something like that) attribute instead of xlink:href for linked offsets -- SVG does not define xlink:href to have meaning for <path> elements.

2. populate the d= attribute of the SPOffset <path> with the offset path, so the SVG requirements are satisfied, and normal SVG UAs have something to render.

[ a ground rule here is that an Inkscape document should look no different in a pure SVG UA than in Inkscape -- at minimum, when in doubt, check how it looks in Batik ]

3. All of the SPOffset extension attributes need to be in the inkscape namespace, not the sodipodi namespace (e.g. inkscape:original, not sodipodi:original). The sodipodi namespace is reserved for Sodipodi's use. This holds true for all new functionality we add.

As interoperability and standards-compliance are core goals for us, I can't sign off on an 0.37 release until these are fixed.

-mental