Comment 9 for bug 404826

Technical note: it seems that in Inkscape the output extension "Cairo PNG" is called when creating the bitmap version (for the system clipboard) of the vector objects copied to the clipboard.

"Cairo PNG" however was used for testing Cairo-based export in Inkscape (i.e. it does not use Inkscape's renderer like 'Export bitmap'), and AFAIU was not intended to replace or be equal in quality to 'File > Export Bitmap'. This internal output extension ("Cairo PNG") does not fully support all SVG features used in Inkscape and always adds a white background. (see also bug #669267).