Inkscape can not blur Bezier line if it is connected to the outer end of a spiral

[ManCaT]

I tried to give a very detailed description on a site of StackExchange:
http://graphicdesign.stackexchange.com/questions/17857/inkscape-can-not-blur-bezier-line-if-it-is-connected-to-the-outer-end-of-a-spira

I was able to test the bug on Linux (Ubuntu 12.04) with these specs: (see also the link above)
Architecture: amd64
InkScape-Version: 0.48.3.1-1ubuntu6.1

and on Mac OS X 10.8.4 with XQuartz 2.7.4
with InkScape Inkscape 0.48.2 r9819

[su_v (suv-lp)]

Technically not a bug - a horizontal (or vertical) line has only one dimension, and the filter effects region thus too (i.e. the blur is not visible).

Workarounds:
- Combine the line with the spiral (the bounding box of the resulting paths as two dimensions), and blur the combined path.
- Group the line with the spiral, and blur the group, instead of the individual objects.

Linking as duplicate to
- Bug #168943 (sf1808103) “Blurring a zero-height or zero-width path” (see comment #2)
  <https://bugs.launchpad.net/inkscape/+bug/168943>

<off-topic>
In the future, please attach sample SVG files directly to the bug report, instead of referring to an off-site page with screenshots only. Having original SVG files available would ease bug triage a lot, and be much appreciated by the members of the Inkscape bug triage team.
</off-topic>