A possible reason for this is that the use of xlink:href, the attribute used to render the text glyphs created by symbol elements in https://wiki.contextgarden.net/images/5/54/layout.svg, has been deprecated since SVG 2.0, as you can see in https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/xlink:href

Instead, as the article recommends, just href should be used instead, and the xlink:href attribute can be preserved as a fallback for (very) old browsers. 


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Los fines no justifican los medios, porque la medida verdadera de nuestro carácter está dada por los medios que estamos dispuestos a utilizar, no por los fines que proclamamos.
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“You develop an instant global consciousness, a people orientation, an intense dissatisfaction with the state of the world, and a compulsion to do something about it. From out there on the moon, international politics look so petty. You want to grab a politician by the scruff of the neck and drag him a quarter of a million miles out and say, ‘Look at that, you son of a bitch.’” — Apollo 14 astronaut Edgar Mitchell