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Viewport for all examples in Firefox is extremely small.
Firefox 21.0 / OSX 10.7
There is apparently a workaround here: #131
Also, might be worth checking that you're using polymaps 2.5.1 - that last release seems to have been updated in github and on the polymaps github website without a commit seeming to stick to any of the source js in the master branch... so I'm not quite sure where the changes are, or if they'll be picked up in a manual build.
I see the SVIG examples on polymaps.org are still broken in Firefox.
It should really just set height/width on the SVG element to 100% when it creates it IMO, as that's all that's required (NB: it doesn't need explicitly display: block and the parent doesn't need explicit position relative, just height and a width values on the SVG to be set to 100%).
While easy to to fix with CSS it's not immediately obvious and trivial to avoid people running into it.
The same error happens on chrome v36
Also, on shadow example the svg filters don't work properly.
I'm seeing this in both Chrome 36 and Firefox 32 on Linux.