Write the author display name alongside the service ID

src/identity/markup.ts

@@ -1,9 +1,31 @@
+const UNSAFE_ATTRIBUTE_VALUE = /["\r\n]|>>/;
+
+/**
+ * Emits `authorId` alongside `author` so a display name survives independently
+ * of the identity provider that minted the ID. Marks whose ID and name are the
+ * same value, or that have only one of the two, keep the single `author`
+ * attribute.
+ */
 export function formatAuthoredComment(
 	content: string,
 	authorId?: string,
+	authorName?: string,
 ): string {
-	if (!authorId || /["\r\n]|>>/.test(authorId)) {
-		return `{>>${content}<<}`;
+	const id = safeAttributeValue(authorId);
+	const name = safeAttributeValue(authorName);
+	if (!id) {
+		return name ? `{{author="${name}">>${content}<<}}` : `{>>${content}<<}`;
 	}
-	return `{{author="${authorId}">>${content}<<}}`;
+	if (!name || name === id) {
+		return `{{author="${id}">>${content}<<}}`;
+	}
+
+	return `{{authorId="${id}" author="${name}">>${content}<<}}`;
+}
+
+function safeAttributeValue(value?: string): string | undefined {
+	const trimmed = value?.trim();
+	if (!trimmed || UNSAFE_ATTRIBUTE_VALUE.test(trimmed)) return undefined;
+
+	return trimmed;
 }

src/main.ts

@@ -1539,7 +1539,11 @@ export default class RelayCommentsPlugin
 		identity: ReviewerIdentity,
 	): string {
 		const content = sanitizeCommentText(comment);
-		return formatAuthoredComment(content, identity.id);
+		return formatAuthoredComment(
+			content,
+			identity.id,
+			identity.source === "fallback" ? undefined : identity.name,
+		);
 	}
 
 	private formatAttachedCommentMarkup(

tests/unit/identity/markup.test.ts

@@ -2,12 +2,24 @@ import { describe, expect, it } from "@jest/globals";
 import { formatAuthoredComment } from "src/identity/markup";
 
 describe("formatAuthoredComment", () => {
-	it("writes only the provider's service ID", () => {
+	it("writes the service ID and the display name", () => {
+		expect(formatAuthoredComment("Looks good", "123456", "Bongo Cat")).toBe(
+			'{{authorId="123456" author="Bongo Cat">>Looks good<<}}',
+		);
+	});
+
+	it("writes only the provider's service ID when no name is available", () => {
 		expect(formatAuthoredComment("Looks good", "123456")).toBe(
 			'{{author="123456">>Looks good<<}}',
 		);
 	});
 
+	it("collapses a name identical to the service ID to one attribute", () => {
+		expect(formatAuthoredComment("Looks good", "Bongo Cat", "Bongo Cat")).toBe(
+			'{{author="Bongo Cat">>Looks good<<}}',
+		);
+	});
+
 	it("supports a literal display name as the author value", () => {
 		expect(formatAuthoredComment("Looks good", "Bongo Cat")).toBe(
 			'{{author="Bongo Cat">>Looks good<<}}',
@@ -23,4 +35,16 @@ describe("formatAuthoredComment", () => {
 			"{>>Looks good<<}",
 		);
 	});
+
+	it("keeps a safe name when only the service ID is unsafe", () => {
+		expect(formatAuthoredComment("Looks good", 'bad"id', "Bongo Cat")).toBe(
+			'{{author="Bongo Cat">>Looks good<<}}',
+		);
+	});
+
+	it("drops an unsafe name and keeps the service ID", () => {
+		expect(formatAuthoredComment("Looks good", "123456", 'bad"name')).toBe(
+			'{{author="123456">>Looks good<<}}',
+		);
+	});
 });