Replicated in Inkscape 0.92.5 (2060ec1f9f, 2020-04-08)
Not replicated in Inkscape 1.1-dev (2135db397d, 2020-10-19) or Inkscape 1.0 (4035a4fb49, 2020-05-01), which give this error instead: InkFileExportCmd::do_export_svg: Object ICON_SPRITE not found in document, nothing to export.
Replicated in Inkscape 0.92.5 (2060ec1f9f, 2020-04-08)
Not replicated in Inkscape 1.1-dev (2135db397d, 2020-10-19) or Inkscape 1.0 (4035a4fb49, 2020-05-01), which give this error instead: InkFileExportCm d::do_export_ svg: Object ICON_SPRITE not found in document, nothing to export.
Closing as fixed in 1.0
Testing on Linux Mint 20