Guide 13.12
Beginner, 4 min read. Checked with Scalpel 1.12.8 on .
In short
A chart that says No candles has no data yet: check the IBKR connection and your market data. A chart area that stays empty with no text is a display problem: on Windows the charts run in Microsoft Edge WebView2, and if that cannot start, Scalpel switches to its built-in chart and says "Chart engine unavailable, using the native chart". A whole window that stays black or blank points at the graphics driver.
On Windows, each desk's chart is drawn with TradingView's free, open-source Lightweight Charts library, in a small WebView2 window that Scalpel places over the chart pane. You need no TradingView account or subscription. On a Mac, and whenever WebView2 is unavailable, Scalpel draws the chart itself. Both show the same candles, VWAP and your stop and target lines.
First, work out which of three problems you have.
The words No candles in the middle of the chart pane mean Scalpel has no bars for this symbol and timeframe yet. The chart itself is fine.
This orange toast appears once, top right, when WebView2 could not start. Scalpel switches every desk to its built-in chart for the rest of the session, so you keep trading with a working chart: candles, VWAP, your stop and target lines, all there.
To get the WebView2 charts back:
WebView2 is part of Windows 11 and comes with Windows 10 updates, but it can be missing or damaged. Download the Evergreen WebView2 Runtime from Microsoft's WebView2 page and run it. In Windows Settings, Apps > Installed apps, it is listed as Microsoft Edge WebView2 Runtime; if it is there, choose Modify then Repair.
Quit Scalpel and delete the folder %APPDATA%\scalpel\data\webview2. It only holds the chart window's browser cache; Scalpel creates it again on the next start. Your settings are not in it.
Scalpel tries WebView2 again at every start. No toast means the WebView2 charts are back.
The WebView2 window started but cannot be seen. The usual cause is a WGPU_BACKEND environment variable set on your computer, often by another program or an old troubleshooting step. Scalpel draws its own window with DirectX 12 (or OpenGL as a fallback) so the chart windows show above it; a Vulkan setting hides them.
Check in Windows: search for Edit environment variables for your account, look for WGPU_BACKEND, delete it, and restart Scalpel.
If the chart sits in the wrong place after you change UI scale in Settings > Appearance or move the window to a monitor with a different Windows display scale, press Ctrl+0 to reset the UI scale to 100%, and restart Scalpel if it stays wrong.
Scalpel draws its interface on the graphics card. A window that never draws at all usually means an old or broken graphics driver.