diff --git a/specs/html5.yaml b/specs/html5.yaml
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+overview: |
+ HTML5 is not namespace-aware. `parametric:…` as an attribute or element name
+ is treated like any other name. Setting the `xmlns` in an HTML5 document
+ is not needed and shouldn’t have any effect on the output.
+
+ This set of tests is only valid in an XML document. SVG embedded in HTML5
+ should pass `./html5.yml` tests instead.
+
+tests:
+ - description: Parametric attributes should work when no namespace is set.
+ document: |
+
+
+
+
+ expected: |
+
+
+
+
+
+ - description: Setting the namespace to something else should have no effect.
+ document: |
+
+
+
+
+ expected: |
+
+
+
+