diff --git a/ui/docs/lobby.md b/ui/docs/lobby.md
index 6620a3f..2edf145 100644
--- a/ui/docs/lobby.md
+++ b/ui/docs/lobby.md
@@ -61,12 +61,20 @@ contents follow the lobby-data store and the account tier:
 | --------------- | --------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------- |
 | `active-past`   | `lobby.my.games.list`                                           | Visible only when the list is non-empty. Empty → the sub-panel is hidden entirely (no empty card surfaces).      |
 | `recruitment`   | `lobby.public.games.list` ⨝ `lobby.my.applications.list`        | Always visible. Public games where the caller is **not** the owner; each card surfaces the caller's application status as a chip (`pending` / `approved` / `rejected` / `unknown`) when there is one. Stale `pending`/`approved` applications on closed games render as standalone "applied" cards; stale `rejected`/`unknown` ones are hidden. |
-| `invitations`   | `lobby.my.invites.list` (status=`pending`)                      | Always visible.                                                                                                  |
+| `invitations`   | `lobby.my.invites.list` (status=`pending`)                      | Visible only when the pending-invites list is non-empty. Empty (or while the fan-out is still in flight) → the sub-panel is hidden, mirroring the `active-past` rule.                                                                                                  |
 | `private games` | `lobby.my.games.list` filtered by `owner_user_id === me` ∧ `game_type === "private"` | Paid tier only (`account.entitlement.is_paid === true`). `VITE_GALAXY_DEV_AFFORDANCES` overrides for DEV bundles. |
 
-Clicking the `games` parent without choosing a sub-panel resolves to
-the first visible sub-panel in the canonical order (e.g. with no
-games yet it lands on `recruitment`).
+Clicking the `games` parent without choosing a sub-panel — or
+arriving on the bare `lobby` alias (a pre-split persisted snapshot,
+or a programmatic `appScreen.go("lobby")`) — resolves to the first
+visible sub-panel in the canonical order. The resolver awaits the
+`lobby.*.list` fan-out and `account` fetch before deciding, so a
+fresh entry with games already in the player's roster lands on
+`active-past`, an invitee-only account lands on `invitations`, and
+the deterministic fallback is `recruitment` (always visible). The
+predicates live in `src/lib/lobby-nav.ts` and are shared between
+this resolver and the sidebar's submenu, so the two surfaces never
+disagree.
 
 ### `recruitment` — inline application form
 
diff --git a/ui/frontend/src/lib/lobby-nav.ts b/ui/frontend/src/lib/lobby-nav.ts
new file mode 100644
index 0000000..6a89667
--- /dev/null
+++ b/ui/frontend/src/lib/lobby-nav.ts
@@ -0,0 +1,66 @@
+// Pure helpers for the lobby `games` submenu.
+//
+// Both the sidebar (`lib/screens/lobby-shell.svelte`) and the bare-`lobby`
+// resolver (`lib/screens/lobby-screen.svelte`) need to agree on which
+// sub-screen is the "first available" — the one auto-expanded in the
+// sidebar and the redirect target when the user lands on the bare lobby
+// alias. Centralising the predicates here keeps the two surfaces from
+// drifting apart.
+//
+// The functions are intentionally pure: they take a resolved snapshot of
+// lobby / account state, return the visible sub-screen list (in canonical
+// order) and the first entry, and never touch stores or globals. Callers
+// derive the state from `lobbyData` / `account` and the DEV-affordances
+// flag.
+
+export type GamesSubScreen =
+	| "games-active-past"
+	| "games-recruitment"
+	| "games-invitations"
+	| "games-private-games";
+
+/**
+ * LobbyNavState is the resolved snapshot of the lobby state the
+ * games-submenu visibility rules depend on. Build it from the live
+ * stores at the call site; the helpers below stay pure on top.
+ */
+export interface LobbyNavState {
+	/** Player has at least one own / past game in `lobby.my-games.list`. */
+	readonly hasMyGames: boolean;
+	/** Player has at least one pending invite in `lobby.invites.list`. */
+	readonly hasInvitations: boolean;
+	/** Player is on a paid tier, or the build exposes DEV affordances. */
+	readonly isPaidOrDev: boolean;
+}
+
+/**
+ * visibleGamesSubScreens returns the games-submenu sub-screens that
+ * are currently visible, in canonical display order:
+ *
+ *   1. `games-active-past` — only when the player has games.
+ *   2. `games-recruitment` — always visible.
+ *   3. `games-invitations` — only when the player has pending invites.
+ *   4. `games-private-games` — only when paid-tier or DEV.
+ *
+ * `games-recruitment` is unconditional, so the returned array is
+ * always non-empty.
+ */
+export function visibleGamesSubScreens(
+	state: LobbyNavState,
+): readonly GamesSubScreen[] {
+	const out: GamesSubScreen[] = [];
+	if (state.hasMyGames) out.push("games-active-past");
+	out.push("games-recruitment");
+	if (state.hasInvitations) out.push("games-invitations");
+	if (state.isPaidOrDev) out.push("games-private-games");
+	return out;
+}
+
+/**
+ * firstVisibleGamesScreen returns the first entry from
+ * `visibleGamesSubScreens(state)`. Since `games-recruitment` is
+ * unconditional, the result is always defined.
+ */
+export function firstVisibleGamesScreen(state: LobbyNavState): GamesSubScreen {
+	return visibleGamesSubScreens(state)[0]!;
+}
diff --git a/ui/frontend/src/lib/screens/games-invitations-screen.svelte b/ui/frontend/src/lib/screens/games-invitations-screen.svelte
index 5199ce7..4338006 100644
--- a/ui/frontend/src/lib/screens/games-invitations-screen.svelte
+++ b/ui/frontend/src/lib/screens/games-invitations-screen.svelte
@@ -35,8 +35,14 @@ accept / decline actions. Accepted invites move the inviting game into
 		actionError = null;
 		try {
 			await redeemInvite(client, invite.gameId, invite.inviteId);
+			// Apply both mutations in the same microtask so the lobby
+			// shell's auto-kick-when-empty effect sees the freshly added
+			// game already in `myGames` when invitations drop to zero —
+			// otherwise the user briefly lands on `recruitment` between
+			// the two writes before the games list catches up.
+			const games = await listMyGames(client);
+			lobbyData.setMyGames(games);
 			lobbyData.removeInvitation(invite.inviteId);
-			lobbyData.setMyGames(await listMyGames(client));
 		} catch (err) {
 			actionError = describeLobbyError(err);
 		} finally {
diff --git a/ui/frontend/src/lib/screens/lobby-screen.svelte b/ui/frontend/src/lib/screens/lobby-screen.svelte
index 8d1624a..884f84b 100644
--- a/ui/frontend/src/lib/screens/lobby-screen.svelte
+++ b/ui/frontend/src/lib/screens/lobby-screen.svelte
@@ -6,24 +6,55 @@ component is what the dispatcher renders when the active screen is
 the historical `lobby` alias (e.g. a snapshot persisted before the
 split, or programmatic `appScreen.go("lobby")` from non-shell code).
 
-The resolver navigates to the first visible games sub-page at mount
-time and renders a thin LobbyShell placeholder while the redirect
-runs. The destination depends on the account tier and on whether the
-caller has any games yet — both are computed by the shell, so we just
-pick `games-recruitment` here as the canonical landing (always
-visible) and let the shell's submenu logic surface the others.
+On mount the resolver awaits the lobby fan-out + account fetch, then
+hands off to `firstVisibleGamesScreen()` — the same helper the shell
+sidebar uses, so the auto-expanded sub-page picked here is the same
+one the sidebar will highlight (e.g. `games-active-past` when the
+player has games, `games-invitations` when there are pending invites
+but no games, etc.). While the data is in flight the user sees the
+lobby chrome with the i18n list-loading placeholder.
 -->
 <script lang="ts">
 	import { onMount } from "svelte";
 	import { appScreen } from "$lib/app-nav.svelte";
 	import { i18n } from "$lib/i18n/index.svelte";
+	import { lobbyData } from "$lib/lobby-data.svelte";
+	import { account } from "$lib/account-store.svelte";
+	import {
+		firstVisibleGamesScreen,
+		type LobbyNavState,
+	} from "$lib/lobby-nav";
 	import LobbyShell from "./lobby-shell.svelte";
 
-	onMount(() => {
-		// The shell's own $effect keeps the user on a valid sub-page if
-		// the resolved choice ever becomes invisible; we just kick off
-		// the redirect on first paint.
-		appScreen.go("games-recruitment");
+	const DEV_AFFORDANCES =
+		import.meta.env.VITE_GALAXY_DEV_AFFORDANCES === "true";
+
+	onMount(async () => {
+		// Bootstrap the lobby client + fan-out; share the in-flight
+		// promise the games-* screens would otherwise kick off.
+		const client = await lobbyData.ensure();
+		// `account.ensure` is required for the paid-tier predicate.
+		// Failures (e.g. transient network blip) fall back to the
+		// non-paid path quietly — `account.current` simply stays null.
+		if (client !== null) {
+			try {
+				await account.ensure(client);
+			} catch {
+				/* not fatal — first-visible falls back to recruitment. */
+			}
+		}
+		const navState: LobbyNavState = {
+			hasMyGames: lobbyData.myGames.length > 0,
+			hasInvitations: lobbyData.invitations.length > 0,
+			isPaidOrDev:
+				DEV_AFFORDANCES || account.current?.entitlement.isPaid === true,
+		};
+		// Guard against the user navigating away mid-await (signOut,
+		// browser Back). If the screen state has changed since mount,
+		// leave it alone.
+		if (appScreen.screen === "lobby") {
+			appScreen.go(firstVisibleGamesScreen(navState));
+		}
 	});
 </script>
 
diff --git a/ui/frontend/src/lib/screens/lobby-shell.svelte b/ui/frontend/src/lib/screens/lobby-shell.svelte
index fb8fe7a..815ffd5 100644
--- a/ui/frontend/src/lib/screens/lobby-shell.svelte
+++ b/ui/frontend/src/lib/screens/lobby-shell.svelte
@@ -8,8 +8,11 @@ F8-04b extends the sidebar to a two-level hierarchy:
 - top-level items: `games` (with submenu), `profile`, and DEV-only
   `synthetic test reports`;
 - `games` submenu: `active-past` (hidden when the player has no games),
-  `recruitment` (always), `invitations` (always), `private games`
-  (paid-tier only; DEV overrides).
+  `recruitment` (always), `invitations` (hidden when no pending invites),
+  `private games` (paid-tier only; DEV overrides). The visibility rules
+  live in `lib/lobby-nav.ts` so the bare-`lobby` resolver
+  (`lobby-screen.svelte`) and this shell agree on the auto-expanded
+  sub-page.
 
 Desktop (>640px): the submenu stays expanded as long as the active
 screen is one of the games sub-panels. Mobile (≤640px, existing
@@ -24,16 +27,17 @@ placeholder.
 -->
 <script lang="ts">
 	import { onMount, type Snippet } from "svelte";
-	import {
-		appScreen,
-		isLobbySubScreen,
-		LOBBY_SUB_SCREENS,
-		type AppScreen,
-	} from "$lib/app-nav.svelte";
+	import { appScreen, isLobbySubScreen, type AppScreen } from "$lib/app-nav.svelte";
 	import { i18n, type TranslationKey } from "$lib/i18n/index.svelte";
 	import { session } from "$lib/session-store.svelte";
 	import { account } from "$lib/account-store.svelte";
 	import { lobbyData } from "$lib/lobby-data.svelte";
+	import {
+		firstVisibleGamesScreen,
+		visibleGamesSubScreens,
+		type GamesSubScreen,
+		type LobbyNavState,
+	} from "$lib/lobby-nav";
 
 	interface Props {
 		children: Snippet;
@@ -44,48 +48,22 @@ placeholder.
 	const DEV_AFFORDANCES =
 		import.meta.env.VITE_GALAXY_DEV_AFFORDANCES === "true";
 
-	type GamesSubId = (typeof LOBBY_SUB_SCREENS)[number];
+	const SUB_LABELS: Record<GamesSubScreen, TranslationKey> = {
+		"games-active-past": "lobby.nav.games.active_past",
+		"games-recruitment": "lobby.nav.games.recruitment",
+		"games-invitations": "lobby.nav.games.invitations",
+		"games-private-games": "lobby.nav.games.private_games",
+	};
 
-	interface GamesSubItem {
-		id: GamesSubId;
-		labelKey: TranslationKey;
-		visible: () => boolean;
-	}
+	let navState = $derived.by<LobbyNavState>(() => ({
+		hasMyGames: lobbyData.myGames.length > 0,
+		hasInvitations: lobbyData.invitations.length > 0,
+		isPaidOrDev:
+			DEV_AFFORDANCES || account.current?.entitlement.isPaid === true,
+	}));
 
-	const GAMES_SUBS: ReadonlyArray<GamesSubItem> = [
-		{
-			id: "games-active-past",
-			labelKey: "lobby.nav.games.active_past",
-			visible: () => lobbyData.myGames.length > 0,
-		},
-		{
-			id: "games-recruitment",
-			labelKey: "lobby.nav.games.recruitment",
-			visible: () => true,
-		},
-		{
-			id: "games-invitations",
-			labelKey: "lobby.nav.games.invitations",
-			visible: () => true,
-		},
-		{
-			id: "games-private-games",
-			labelKey: "lobby.nav.games.private_games",
-			visible: () =>
-				DEV_AFFORDANCES || account.current?.entitlement.isPaid === true,
-		},
-	];
-
-	function visibleGamesSubs(): ReadonlyArray<GamesSubItem> {
-		return GAMES_SUBS.filter((sub) => sub.visible());
-	}
-
-	function firstVisibleGamesScreen(): AppScreen {
-		const visible = visibleGamesSubs();
-		// recruitment is unconditionally visible, so visible is never
-		// empty — but keep the fallback for type safety.
-		return visible[0]?.id ?? "games-recruitment";
-	}
+	let visibleSubs = $derived(visibleGamesSubScreens(navState));
+	let firstVisible = $derived(firstVisibleGamesScreen(navState));
 
 	function gotoScreen(screen: AppScreen): void {
 		if (appScreen.screen !== screen) {
@@ -94,11 +72,20 @@ placeholder.
 	}
 
 	function gotoGamesParent(): void {
-		gotoScreen(firstVisibleGamesScreen());
+		gotoScreen(firstVisible);
 	}
 
-	let activeGamesSub = $derived.by<GamesSubItem | null>(() => {
-		return GAMES_SUBS.find((s) => s.id === appScreen.screen) ?? null;
+	let activeGamesSub = $derived.by<GamesSubScreen | null>(() => {
+		const s = appScreen.screen;
+		if (
+			s === "games-active-past" ||
+			s === "games-recruitment" ||
+			s === "games-invitations" ||
+			s === "games-private-games"
+		) {
+			return s;
+		}
+		return null;
 	});
 
 	let gamesActive = $derived.by(() => isLobbySubScreen(appScreen.screen));
@@ -171,11 +158,11 @@ placeholder.
 		const screen = appScreen.screen;
 		if (screen === "games-private-games") {
 			if (!DEV_AFFORDANCES && account.current?.entitlement.isPaid !== true) {
-				appScreen.go(firstVisibleGamesScreen());
+				appScreen.go(firstVisible);
 			}
 		} else if (screen === "synthetic-reports") {
 			if (!DEV_AFFORDANCES) {
-				appScreen.go(firstVisibleGamesScreen());
+				appScreen.go(firstVisible);
 			}
 		} else if (screen === "games-active-past") {
 			// Hide-when-empty is asymmetric: we only kick the user out if
@@ -184,7 +171,17 @@ placeholder.
 			// fresh navigation would bounce off this screen before the
 			// fan-out resolves.
 			if (!lobbyData.loading && lobbyData.myGames.length === 0) {
-				appScreen.go(firstVisibleGamesScreen());
+				appScreen.go(firstVisible);
+			}
+		} else if (screen === "games-invitations") {
+			// Same asymmetric rule as `games-active-past`: hide-when-empty
+			// fires only after the fan-out resolves, so a fresh nav onto
+			// invitations does not bounce while the list is still loading.
+			// An invite redeemed / declined from this screen drops the
+			// only pending entry → user is moved to the first visible
+			// sub-page on the next tick.
+			if (!lobbyData.loading && lobbyData.invitations.length === 0) {
+				appScreen.go(firstVisible);
 			}
 		}
 	});
@@ -225,17 +222,17 @@ placeholder.
 						class="submenu desktop-only"
 						aria-label={i18n.t("lobby.nav.games.aria_label")}
 					>
-						{#each visibleGamesSubs() as sub (sub.id)}
+						{#each visibleSubs as sub (sub)}
 							<li>
 								<button
 									type="button"
 									class="nav-link sub"
-									class:active={appScreen.screen === sub.id}
-									aria-current={appScreen.screen === sub.id ? "page" : undefined}
-									onclick={() => gotoScreen(sub.id)}
-									data-testid="lobby-nav-{sub.id}"
+									class:active={appScreen.screen === sub}
+									aria-current={appScreen.screen === sub ? "page" : undefined}
+									onclick={() => gotoScreen(sub)}
+									data-testid="lobby-nav-{sub}"
 								>
-									{i18n.t(sub.labelKey)}
+									{i18n.t(SUB_LABELS[sub])}
 								</button>
 							</li>
 						{/each}
@@ -258,9 +255,9 @@ placeholder.
 							data-testid="lobby-nav-games-mobile"
 						>
 							{i18n.t("lobby.nav.games.mobile_toggle", {
-								label: activeGamesSub
-									? i18n.t(activeGamesSub.labelKey)
-									: i18n.t("lobby.nav.games.recruitment"),
+								label: i18n.t(
+									SUB_LABELS[activeGamesSub ?? "games-recruitment"],
+								),
 							})}
 							<span aria-hidden="true">▾</span>
 						</button>
@@ -270,18 +267,18 @@ placeholder.
 								role="listbox"
 								aria-label={i18n.t("lobby.nav.games.aria_label")}
 							>
-								{#each visibleGamesSubs() as sub (sub.id)}
+								{#each visibleSubs as sub (sub)}
 									<li>
 										<button
 											type="button"
 											class="popover-item"
-											class:active={appScreen.screen === sub.id}
+											class:active={appScreen.screen === sub}
 											role="option"
-											aria-selected={appScreen.screen === sub.id}
-											onclick={() => selectMobileSub(sub.id)}
-											data-testid="lobby-nav-{sub.id}-mobile"
+											aria-selected={appScreen.screen === sub}
+											onclick={() => selectMobileSub(sub)}
+											data-testid="lobby-nav-{sub}-mobile"
 										>
-											{i18n.t(sub.labelKey)}
+											{i18n.t(SUB_LABELS[sub])}
 										</button>
 									</li>
 								{/each}
diff --git a/ui/frontend/tests/lobby-nav.test.ts b/ui/frontend/tests/lobby-nav.test.ts
new file mode 100644
index 0000000..63eb512
--- /dev/null
+++ b/ui/frontend/tests/lobby-nav.test.ts
@@ -0,0 +1,114 @@
+// Pure-state coverage for the lobby `games` submenu visibility rules.
+// The same helper drives the sidebar's auto-expanded sub-item and the
+// bare-`lobby` resolver's redirect target; if they ever disagree the
+// player lands on the wrong sub-page on entry.
+
+import { describe, expect, test } from "vitest";
+
+import {
+	firstVisibleGamesScreen,
+	visibleGamesSubScreens,
+	type LobbyNavState,
+} from "../src/lib/lobby-nav";
+
+function state(overrides: Partial<LobbyNavState> = {}): LobbyNavState {
+	return {
+		hasMyGames: false,
+		hasInvitations: false,
+		isPaidOrDev: false,
+		...overrides,
+	};
+}
+
+describe("visibleGamesSubScreens", () => {
+	test("free-tier player with nothing — only recruitment is visible", () => {
+		expect(visibleGamesSubScreens(state())).toEqual(["games-recruitment"]);
+	});
+
+	test("player with games — active-past leads recruitment", () => {
+		expect(visibleGamesSubScreens(state({ hasMyGames: true }))).toEqual([
+			"games-active-past",
+			"games-recruitment",
+		]);
+	});
+
+	test("player with pending invites — invitations appears after recruitment", () => {
+		expect(visibleGamesSubScreens(state({ hasInvitations: true }))).toEqual([
+			"games-recruitment",
+			"games-invitations",
+		]);
+	});
+
+	test("paid / DEV tier — private-games tails the list", () => {
+		expect(visibleGamesSubScreens(state({ isPaidOrDev: true }))).toEqual([
+			"games-recruitment",
+			"games-private-games",
+		]);
+	});
+
+	test("all four flags on — full canonical order", () => {
+		expect(
+			visibleGamesSubScreens(
+				state({
+					hasMyGames: true,
+					hasInvitations: true,
+					isPaidOrDev: true,
+				}),
+			),
+		).toEqual([
+			"games-active-past",
+			"games-recruitment",
+			"games-invitations",
+			"games-private-games",
+		]);
+	});
+
+	test("recruitment is always present regardless of input", () => {
+		const variants: LobbyNavState[] = [
+			state(),
+			state({ hasMyGames: true }),
+			state({ hasInvitations: true }),
+			state({ isPaidOrDev: true }),
+			state({ hasMyGames: true, hasInvitations: true, isPaidOrDev: true }),
+		];
+		for (const v of variants) {
+			expect(visibleGamesSubScreens(v)).toContain("games-recruitment");
+		}
+	});
+});
+
+describe("firstVisibleGamesScreen", () => {
+	test("free-tier nothing → recruitment", () => {
+		expect(firstVisibleGamesScreen(state())).toBe("games-recruitment");
+	});
+
+	test("player with games → active-past wins", () => {
+		expect(firstVisibleGamesScreen(state({ hasMyGames: true }))).toBe(
+			"games-active-past",
+		);
+	});
+
+	test("invitee-only (no games yet) → recruitment still wins over invitations by canonical order", () => {
+		// Pending invites do NOT promote `invitations` above `recruitment`;
+		// the canonical order places `recruitment` second only to
+		// `active-past`. This guards against accidentally re-ordering the
+		// sub-items in a way that surprises invitee-only sessions.
+		expect(firstVisibleGamesScreen(state({ hasInvitations: true }))).toBe(
+			"games-recruitment",
+		);
+	});
+
+	test("games + invites → active-past still wins", () => {
+		expect(
+			firstVisibleGamesScreen(
+				state({ hasMyGames: true, hasInvitations: true }),
+			),
+		).toBe("games-active-past");
+	});
+
+	test("paid tier with no games → recruitment, not private-games", () => {
+		expect(firstVisibleGamesScreen(state({ isPaidOrDev: true }))).toBe(
+			"games-recruitment",
+		);
+	});
+});