Created attachment 263332 [details]
Screenshot of the issue.
Reproduced with WebKitGTK+ 2.10.0 and with Safari 7.1 on OS X Mavericks.
Steps to reproduce the problem:
Open the URL:
What is the expected behavior?
All the SVGs are shown as the included PNG as reference
What went wrong?
Only the SVGs in which the feImage provides explicit values for x=0, y=0, width=100% and height=100% are shown correctly.
The 2 SVGs in which this values are not provided for the feImage (the defaults are as explained above) are not displayed properly.
Funnily enough, the render is yet different depending on whether the embedded SVG document provides a "viewBox" attribute.
If the viewBox is not explicit, the feImage shows proper proportions but the origin seems to be in the left top corner of the filter region (x=-10%, y=-10%).
If the viewBox is explicit to the width and height values of the embedded SVG document (which, AFAIK, is the default), the proportions are also wrong.
Similar issues in other web engines: