combined blur and opacity result in overly exaggerated opacity

[Thomas Bartosik]

When adding blur AND (low values, like 10%) opacity to an object, the resulting pdf export has hardly any visible remains of the object.
I don't know it this is related, but there are some other blur/opacity problems as well in this document (please tell me open a different bug report if they're not related):
1) Notice the different color (lightness I would say) of the two boxes in the resulting pdf
2) Notice the hardly existing blur around the box that has the mask applied to it in the resulting pdf
3) Notice the colorful stripes at the edges of the boxes (compress image if you can't see them); the ..._artifacts.png image attached shows this as well. It's also clear there's something wrong with the blur as the outline of the text comes out. if something should show up, then the center and not the edge as the blur should fall of the farther off the pixel is from the object's center. Are the artifacts caused by compression? Are images jpg or zip compressed in the pdf output?

4) Everything is as expected when exporting the whole page as a png. Is there something wrong with my pdf-export/cairo/pdf-viewers or can you see this as well?
I am on 64bit gentoo, current as of today.
Inkscape 0.48, 0.48.2 and the bazaar revision 10549 that was used to create those files (current as of today as well) show the same behavior, although I am under the impression that the bzr version handles the blur a tad better.

[su_v (suv-lp)]

Duplicate of Bug #381677 “Exporting to PDF problems (reduced opacity + filter effect)”?
<https://bugs.launchpad.net/inkscape/+bug/381677>

[su_v (suv-lp)]

Thank you for taking the time to analyze & provide a reduced test case, as well as for confirming that bug #381677 had reported the same issue earlier. I will link this report as a duplicate to bug #381677 to allow easier tracking of any progress and keep the discussion in one place.

Please add a comment here and revert the duplicate status if you don't agree or have additional information indicating that these are different issues.