Browser backend selection.
"webkit"(default): WKWebView. macOS only. Zero external dependencies — uses the system WebKit.framework."chrome": Chrome/Chromium via DevTools Protocol over--remote-debugging-pipe. Works anywhere Chrome is installed. Auto-detects the binary in standard locations; override withbackend.pathor theBUN_CHROME_PATHenvironment variable.
The object form lets you pass extra launch flags. Chrome switches are last-wins for duplicates, so argv can override the defaults.
Chrome is spawned once per process — the first new Bun.WebView() call's path/argv/dataStore.directory win; subsequent views reuse the same Chrome instance via Target.createTarget.
Default flags: --remote-debugging-pipe --headless --no-first-run --no-default-browser-check --disable-gpu --user-data-dir=<temp>.