SVGHMI: Fix browser side exception when some widget are not used, and are then discarded and not present in final SVG. In that case JS code was still making reference to discarded widget elements and was raising exception at init.
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<dc:format>image/svg+xml</dc:format>
<dc:type
rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
<dc:title />
</cc:Work>
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<desc
id="desc_page0">This is description for page 0
all lines in the form "name: value"
are used as js object definition initializer
role: "page"
name: "Home"
after triple opening braces is global JavaScript code
{{{
/* JS style Comment */
alert("Hello World");
}}}
after triple closing braces is back to description
</desc>
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xml:space="preserve"
style="font-style:normal;font-weight:normal;font-size:160px;line-height:125%;font-family:sans-serif;letter-spacing:0px;word-spacing:0px;fill:#ffffff;fill-opacity:1;stroke:none;stroke-width:1px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1"
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format: "%4.4d"</desc><tspan
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y="418.24219"
style="stroke-width:1px">8888</tspan></text>
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