Re: [svgwg] Clarify that SVG does not need to be valid XML (#960)

I agree with the original report. The current wording in the conformance section is misleading because it suggests that SVG content may need to be _valid XML_, while in practice and in the rest of the specification only _well‑formed XML_ is required.

### Why this matters

* SVG 2 does not define or rely on any DTD.
Therefore, XML _validity_ (in the XML 1.0 sense) is not a meaningful conformance criterion.
* Browsers do not perform DTD‑based validation when parsing SVG.
* None of the examples in the specification include a `<!DOCTYPE>` declaration, which would be required for XML validity.
* Likewise, the examples do not include an XML declaration (`<?xml version="1.0"?>`), and authors are not expected to use one.
Both constructs are unnecessary and often undesirable in real‑world SVG usage.

### What authors actually need

SVG content must be **well‑formed XML**, meaning:
* elements are properly nested,
* attributes are correctly quoted,
* there is a single root element,
* no invalid characters appear,
* etc.

But SVG content **does not need to be valid XML**, and the specification should not imply otherwise.

### Suggested clarification for the conformance section

Here are two possible formulations that would make the intent unambiguous:

**Option A (more explicit and author‑friendly)**

SVG content is required to be _well‑formed XML_.
SVG content is not required to be _valid XML_, and user agents do not perform DTD‑based validation.
In particular, SVG documents do not need a `<!DOCTYPE>` declaration or an XML declaration (`<?xml …?>`).

**Option B (spec‑style explanatory note)**

**Note:** 
SVG is defined using XML syntax, but conformance only requires _well‑formedness_.
XML validity (i.e., DTD‑based validation) is not required for SVG documents, and including a DOCTYPE or XML declaration is neither necessary nor recommended.

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Received on Thursday, 16 April 2026 23:45:59 UTC