Object or image disappear when adding a color matrix in the filters editor

Please add information about OS/platform and Inkscape version (revision if related to recent trunk) to the bug description.

On OS X 10.7.5:
- not reproduced with Inkscape 0.48.5 r10040
- reproduced with Inkscape 0.91 r13725
- reproduced with Inkscape 0.91+devel r13955, r13956, r13968

Regression not related to recent breakage in trunk (bug #1429114).

On Kubuntu 14.04. Was already there On Kubuntu 12.04.

Based on tests with local builds of older revisions:
- not reproduced with 0.48+devel r10325
- reproduced with 0.48+devel r10326
this regression seems to have been introduced with the merge of the new cairo renderer in rev 10326.

Adding the Color Matrix filter primitive via GUI creates this filter definition (same in 0.48 as in latest trunk):

      <feColorMatrix
         id="feColorMatrix4197" />

Editing the matrix afterwards (via GUI) results in:

      <feColorMatrix
         id="feColorMatrix4197"
         values="1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 " />

Both Chromium and Batik 1.7 (Squiggle) render both effects with visible output, whereas the new cairo renderer apparently does not produce output unless the feColorMatrix node has a 'values' attribute.

<quote src="SVG 1.1 specification">
* type = "matrix | saturate | hueRotate | luminanceToAlpha"
(...). If attribute ‘type’ is not specified, then the effect is as if a value of matrix were specified. (...)

* values = "list of <number>s"
(...). If the attribute is not specified, then the default behavior depends on the value of attribute ‘type’. If type="matrix", then this attribute defaults to the identity matrix. (...)
</quote>
http://www.w3.org/TR/SVG11/filters.html#feColorMatrixElement

The same occors when you create a new empty (without any primitive) filter with the GUI and apply it to the object. I remember now this apppeared when Cairo was implemented.

Hi - thanks for reporting this bug, still no progress unfortunately.

As part of migration to Inkscape's new bug tracker on GitLab, I've closed the issue here. It can still be tracked at https://gitlab.com/inkscape/inkscape/-/issues/1638

Please feel free to file new bugs about the issues you're seeing at http://inkscape.org/report.