diff --git a/src/richtext/htmlAsRichText.ts b/src/richtext/htmlAsRichText.ts
index 6d60c608..b3cadf1a 100644
--- a/src/richtext/htmlAsRichText.ts
+++ b/src/richtext/htmlAsRichText.ts
@@ -21,7 +21,7 @@ export const htmlAsRichText = (
 	config?: AsRichTextConfig,
 ): AsRichTextReturnType => {
 	const { result, messages } = unified()
-		.use(rehypeParse, { emitParseErrors: true })
+		.use(rehypeParse, { emitParseErrors: true, missingDoctype: 0 })
 		.use(rehypeRichText, config)
 		.processSync(html);
 
diff --git a/test/__testutils__/testAsRichTextHelper.ts b/test/__testutils__/testAsRichTextHelper.ts
index b0636b54..c68d519f 100644
--- a/test/__testutils__/testAsRichTextHelper.ts
+++ b/test/__testutils__/testAsRichTextHelper.ts
@@ -9,6 +9,11 @@ type TestAsRichTextHelperArgs = {
 
 	config?: AsRichTextConfig;
 
+	/**
+	 * Warnings that are expected to be present in the output.
+	 */
+	expectWarnings?: string[];
+
 	/**
 	 * The rich text format is a lossy representation of HTML. Namely it does not
 	 * preserves indentation and applies some optimizations to the output such as
@@ -55,6 +60,10 @@ const testAsRichTextHelperFactory = (
 			},
 		});
 
+		expect(
+			output.warnings.map((warning) => warning.message).sort(),
+		).toStrictEqual(args.expectWarnings?.sort() ?? []);
+
 		if (!args.expectAsHTMLNotToMatchInput) {
 			expect(outputAsHTML).toBe(args.input);
 		} else {
diff --git a/test/richtext/__snapshots__/htmlAsRichText.test.ts.snap b/test/richtext/__snapshots__/htmlAsRichText.test.ts.snap
index 4bde42f1..af6c5642 100644
--- a/test/richtext/__snapshots__/htmlAsRichText.test.ts.snap
+++ b/test/richtext/__snapshots__/htmlAsRichText.test.ts.snap
@@ -472,6 +472,8 @@ exports[`transforms HTML to rich text > embed > iframe 1`] = `
 ]
 `;
 
+exports[`transforms HTML to rich text > embed > missing src 1`] = `[]`;
+
 exports[`transforms HTML to rich text > image > empty alt 1`] = `
 [
   {
@@ -688,6 +690,8 @@ exports[`transforms HTML to rich text > image > missing alt 1`] = `
 ]
 `;
 
+exports[`transforms HTML to rich text > image > missing src 1`] = `[]`;
+
 exports[`transforms HTML to rich text > image > non-prismic 1`] = `
 [
   {
@@ -1002,6 +1006,17 @@ exports[`transforms HTML to rich text > spans > hyperlink 1`] = `
 ]
 `;
 
+exports[`transforms HTML to rich text > spans > hyperlink missing href 1`] = `
+[
+  {
+    "direction": "ltr",
+    "spans": [],
+    "text": "lorem ipsum dolor sit amet",
+    "type": "paragraph",
+  },
+]
+`;
+
 exports[`transforms HTML to rich text > spans > label 1`] = `
 [
   {
diff --git a/test/richtext/htmlAsRichText.test.ts b/test/richtext/htmlAsRichText.test.ts
index 1951c71c..fa2e5429 100644
--- a/test/richtext/htmlAsRichText.test.ts
+++ b/test/richtext/htmlAsRichText.test.ts
@@ -33,6 +33,14 @@ describe("transforms HTML to rich text", () => {
 			input: /* html */ `<p>lorem <a href="https://prismic.io">ipsum</a> dolor <a href="https://prismic.io" target="_blank">sit</a> amet</p>`,
 		});
 
+		testHTMLAsRichTextHelper("hyperlink missing href", {
+			input: /* html */ `<p>lorem <a>ipsum</a> dolor sit amet</p>`,
+			expectWarnings: [
+				"Element of type `hyperlink` is missing an `href` attribute",
+			],
+			expectAsHTMLNotToMatchInput: true,
+		});
+
 		testHTMLAsRichTextHelper("nested spans", {
 			input: /* html */ `<p>lorem <strong>ips<em>um <a href="https://prismic.io">dolor</a></em></strong> sit amet</p>`,
 		});
@@ -119,6 +127,12 @@ describe("transforms HTML to rich text", () => {
 			expectAsHTMLNotToMatchInput: true,
 		});
 
+		testHTMLAsRichTextHelper("missing src", {
+			input: /* html */ `<img />`,
+			expectWarnings: ["Element of type `img` is missing an `src` attribute"],
+			expectAsHTMLNotToMatchInput: true,
+		});
+
 		describe("extracts image in text nodes and resume previous text node", () => {
 			testHTMLAsRichTextHelper("basic", {
 				input: /* html */ `<p>lorem ipsum <img src="https://example.com/foo.png" alt="bar" /> dolor sit amet</p>`,
@@ -153,6 +167,12 @@ describe("transforms HTML to rich text", () => {
 			input: /* html */ `<blockquote class="twitter-tweet" src="https://twitter.com/li_hbr/status/1803718142222282829?ref_src=twsrc%5Etfw"><p lang="en" dir="ltr">Slack bot that uses AI to tl;dr; threads for you, anyone?</p>— Lucie (@li_hbr) <a href="https://twitter.com/li_hbr/status/1803718142222282829?ref_src=twsrc%5Etfw">June 20, 2024</a></blockquote>`,
 			config: { serializer: { blockquote: "embed" } },
 		});
+
+		testHTMLAsRichTextHelper("missing src", {
+			input: /* html */ `<iframe></iframe>`,
+			expectWarnings: ["Element of type `embed` is missing an `src` attribute"],
+			expectAsHTMLNotToMatchInput: true,
+		});
 	});
 
 	describe("configuration", () => {
@@ -224,7 +244,7 @@ describe("transforms HTML to rich text", () => {
 				});
 
 				testHTMLAsRichTextHelper("image node", {
-					input: /* html */ `<foo src="https://example.com/foo.png" alt="foo" />`,
+					input: /* html */ `<foo src="https://example.com/foo.png" alt="foo"></foo>`,
 					config: {
 						serializer: {
 							foo: () => ({
@@ -242,7 +262,7 @@ describe("transforms HTML to rich text", () => {
 				});
 
 				testHTMLAsRichTextHelper("embed node", {
-					input: /* html */ `<foo src="https://example.com/foo.png" />`,
+					input: /* html */ `<foo src="https://example.com/foo.png"></foo>`,
 					config: {
 						serializer: {
 							foo: () => ({
@@ -465,27 +485,3 @@ describe("transforms HTML to rich text", () => {
 		});
 	});
 });
-
-type WarnCase = {
-	name: string;
-	input: string;
-};
-
-it.each<WarnCase>([
-	{
-		name: "element of type `img` is missing an `src` attribute",
-		input: /* html */ `<img>`,
-	},
-	{
-		name: "element of type `embed` is missing an `src` attribute",
-		input: /* html */ `<iframe>lorem ipsum dolor sit amet</iframe>`,
-	},
-	{
-		name: "element of type `hyperlink` is missing an `href` attribute",
-		input: /* html */ `<p><a>missing-hyperlink-href</a></p>`,
-	},
-])("warns on unprocessable elements ($name)", ({ name, input }) => {
-	const output = htmlAsRichText(input);
-
-	expect(output.warnings.toString()).toMatch(new RegExp(name, "i"));
-});