If the user played multiplayer earlier in the tab session, room-code,
room-token, and player-color persisted in sessionStorage. Clicking Play
Solo then:
1. navigate('/game') — no code param
2. GameRoute reads sessionStorage, finds stale creds → Case 1
canonicalises the URL to /game/<stale-code>
3. MultiplayerGameView mounts, opens a WS to a dead room, handshake
fails silently → blank white screen with a live URL like
/game/OSJBJY in the address bar.
Fix: handlePlaySolo explicitly wipes room-code, room-token, player-color,
layout-name, and modifier-profile-name before navigating. The solo path
then goes through GameRoute's Case 2 (no code, no creds) and mounts
GameView cleanly.
Regression test in solo-smoke.spec.ts seeds sessionStorage with stale
MP creds, clicks Play Solo, and asserts:
- URL settles on /game (not /game/<stale>)
- No 'mp-joining' placeholder
- Board renders (e2 pawn visible)
- All stale keys are wiped from sessionStorage
- No console errors
Verified the test fails without the fix (Playwright hits the blank
screen / Joining placeholder) and passes with it.
Joey Yakimowich-Payne
6e0479703d