Chess Sidebar

Keep your chess game beside whatever else you're doing.

Chess Sidebar puts supported Chess.com and Lichess games in Chrome's side panel, so you can play while reading, watching, scrolling, or working without hunting for the original game tab.

500+ games played through it

Chrome 114+ · Chess.com Live Chess · supported Lichess Board API games · no engine, no advice

chess.com the real game, in a tab you left behind
Chess Sidebar the side panel, open wherever you are

What it's for

Chess has a lot of waiting in it.

A 15|10 game is mostly your opponent's clock. Chess Sidebar is for the players who spend that time doing something else — and who lose games to a tab they forgot to go back to.

Keep the tab you're in

Your game doesn't have to be the window in front of you. Read, write, or watch in the main tab; the panel stays open beside all of them.

Notice it's your turn

The panel updates the moment your opponent moves. If you'd rather not keep a panel open, Chess Sidebar can pop a small window instead — and it won't take your focus unless you tell it to.

Premove while they think

The mirror board stays live during your opponent's clock. Queue one move; it's re-checked against the new position and sent the instant their move lands.

How it works

Open a game. Then get on with your day.

Choose a platform and the game comes to you.

For Chess.com, start a Live Chess game normally. For Lichess, select Lichess in the panel and connect your account through its official authorization page.

Click the Chess Sidebar icon. Your board appears in Chrome's side panel, beside whatever else is on screen.

Go wherever you were going. Another tab, YouTube, your inbox, work. The panel stays put, and so does your game.

When your opponent moves, the panel shows it. Play your reply right there in the panel—no need to find the original game.

Your move goes to the real game through the Chess.com tab or Lichess's official Board API. Same game, same clock, same rating.

How the Chess.com connection works underneath
chess.com tab

Your live game. It stays open, it stays real, and it stays the only thing the server ever sees.

game id · TCN move codes · clocks
network tap

A small script watches the play-service socket the page already opened. It adds nothing to the page, and forwards no raw frames, headers or cookies — only the moves and the clocks.

sanitized snapshot
service worker

The hub. It keeps the latest snapshot and hands it to whichever window you have open.

position · clocks · whose turn
side panel

The mirror board and your input. Your move is applied here first, so the board answers straight away and reconciles afterwards.

from square → to square
content script

Replays your move on the real board as a pointer drag, then confirms it landed by watching the board itself rather than trusting a delay.

pointerdown → pointermove ×4 → pointerup
the real board

The move is now just a move. Same game, same server, same rating.

Limits

Five things it will not do.

It never touches the page

chess.com fingerprints extensions by looking for the elements they inject into the board. Chess Sidebar injects none. Every pixel of its interface lives in the panel, where the page can't see it.

It never waits on a timer

Chrome throttles timers and stops animation frames in hidden tabs — which is exactly the situation this extension exists for. A move is dispatched in one synchronous burst, and anything that genuinely has to wait waits on a DOM change instead.

It never guesses your position

A move is rolled back only on evidence: a later snapshot that still doesn't contain it. A backgrounded tab that hasn't repainted yet is not a failed move, and it isn't treated as one.

It has no engine

Nothing here evaluates a position, suggests a move, or plays for you. It shows you the game you're already allowed to see, and sends the move you already chose.

It will not bypass Lichess's API limits

Lichess support uses OAuth and the official Board API. Rapid, Classical and Correspondence are supported; Lichess permits Blitz only for direct challenges, AI games and bulk pairings. Ordinary pool Bullet and Blitz are not automated.