Revision control
++ <svg xmlns="http://www.w3.org/2000/svg" width="420" height="300">
++ <defs>
++ <g id="opacityTest">
++ <text style="font-size: 60px; font-weight: bold; font-family: sans-serif; fill: black; stroke: red; stroke-width:3.1px;">Qt Svg</text>
++ <text y="70" stroke-opacity="0.7" style="font-size: 60px; font-weight: bold; font-family: sans-serif; fill: black; stroke: red; stroke-width:3.1px;">Qt Svg</text>
++ <text y="140" fill-opacity="0.7" style="font-size: 60px; font-weight: bold; font-family: sans-serif; fill: black; stroke: red; stroke-width:3.1px;">Qt Svg</text>
++ <text y="210" fill-opacity="0.7" stroke-opacity="0.7" style="font-size: 60px; font-weight: bold; font-family: sans-serif; fill: black; stroke: red; stroke-width:3.1px;">Qt Svg</text>
++ </g>
++ </defs>
++ <use href="#opacityTest" transform="translate(5, 70)"/>
++ <use href="#opacityTest" transform="translate(215, 70)" opacity="0.7"/>
++ </svg>