Fix PR and issue detail tab titles

apps/dashboard/src/components/issues/detail/issue-detail-page.tsx

@@ -15,6 +15,7 @@ import {
 import { githubRevalidationSignalKeys } from "#/lib/github-revalidation";
 import { useGitHubSignalStream } from "#/lib/use-github-signal-stream";
 import { useHasMounted } from "#/lib/use-has-mounted";
+import { usePageTitle } from "#/lib/use-page-title";
 import { useRegisterTab } from "#/lib/use-register-tab";
 import { IssueDetailActivitySection } from "./issue-detail-activity";
 import { getIssueStateConfig, IssueDetailHeader } from "./issue-detail-header";
@@ -89,6 +90,8 @@ export function IssueDetailContent({
 	const commentPagination = pageQuery.data?.commentPagination;
 	const eventPagination = pageQuery.data?.eventPagination;
 
+	usePageTitle(issue?.title);
+
 	useRegisterTab(
 		registerTab && issue
 			? {

apps/dashboard/src/components/pulls/detail/pull-detail-page.tsx

@@ -17,6 +17,7 @@ import {
 import { githubRevalidationSignalKeys } from "#/lib/github-revalidation";
 import { useGitHubSignalStream } from "#/lib/use-github-signal-stream";
 import { useHasMounted } from "#/lib/use-has-mounted";
+import { usePageTitle } from "#/lib/use-page-title";
 import { useRegisterTab } from "#/lib/use-register-tab";
 import { PullBodySection } from "./pull-body-section";
 import { PullDetailActivitySection } from "./pull-detail-activity";
@@ -123,6 +124,8 @@ export function PullDetailContent({
 	const headRefDeleted = pageQuery.data?.headRefDeleted ?? false;
 	const viewer = viewerQuery.data ?? null;
 
+	usePageTitle(pr?.title);
+
 	useRegisterTab(
 		registerTab && pr
 			? {

apps/dashboard/src/components/pulls/review/review-page.tsx

@@ -51,6 +51,7 @@ import type {
 } from "#/lib/github.types";
 import { githubRevalidationSignalKeys } from "#/lib/github-revalidation";
 import { useGitHubSignalStream } from "#/lib/use-github-signal-stream";
+import { usePageTitle } from "#/lib/use-page-title";
 import { useRegisterTab } from "#/lib/use-register-tab";
 import { checkPermissionWarning } from "#/lib/warning-store";
 import type { ReviewDiffPaneHandle } from "./review-diff-pane";
@@ -220,6 +221,8 @@ export function ReviewPage() {
 	);
 	const reviewComments = reviewCommentsQuery.data ?? [];
 
+	usePageTitle(pr ? `Review: ${pr.title}` : null);
+
 	// ── Mention support for inline comment forms ──────────────────────
 	const [mentionActivated, setMentionActivated] = useState(false);
 	const viewerQuery = useQuery(githubViewerQueryOptions(scope));

apps/dashboard/src/lib/seo.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { buildSeo, summarizeText, toAbsoluteUrl } from "./seo";
+import { buildSeo, formatPageTitle, summarizeText, toAbsoluteUrl } from "./seo";
 
 describe("summarizeText", () => {
 	it("strips basic markdown and whitespace", () => {
@@ -46,3 +46,13 @@ describe("buildSeo", () => {
 		});
 	});
 });
+
+describe("formatPageTitle", () => {
+	it("adds the app name when it is missing", () => {
+		expect(formatPageTitle("Fix tab titles")).toBe("Fix tab titles | DiffKit");
+	});
+
+	it("does not duplicate the app name", () => {
+		expect(formatPageTitle("Inbox | DiffKit")).toBe("Inbox | DiffKit");
+	});
+});

apps/dashboard/src/lib/use-page-title.ts

@@ -0,0 +1,9 @@
+import { useEffect } from "react";
+import { formatPageTitle } from "./seo";
+
+export function usePageTitle(title: string | null | undefined) {
+	useEffect(() => {
+		if (!title) return;
+		document.title = formatPageTitle(title);
+	}, [title]);
+}