Created attachment 145216 [details]
Gwenview fails to show text on svg

Currently Gwenview uses Qt SVG library (QSvgRenderer) to display SVG files, the problem is that Qt supports only SVG 1.2 Tiny which is a minimal and restricted subset of the full SVG standard, for example if you use tpan elements you can't see that text on Gwenview (see attached image).
Many diagram and vector editors (like LibreOffice Draw and Inkscape) uses multiples essential SVG elements outside SVG 1.2 Tiny to enable more styling and powerful features, and it seems Qt team is not interested in adding support to full SVG standard https://bugreports.qt.io/browse/QTBUG-61677
The optimal solution would be to embed an external viewer (like Qt WebEngine or inkview) to make Gwenview more capable of responding to SVG upgrades.