Playwright & Chromium

Deskapp bundles Playwright plumbing so backend features can drive a real Chromium (play a site, browser automation, future screenshots/testing). The chromium facade on @/core/facade.ts is the entry point — see chromium API for the launch pattern.

Resolving Chromium

chromium.resolve() locates a usable Chromium binary. Candidates, in order:

1. DESKAPP_CHROMIUM environment variable — a user- or CI-provided binary.
2. Bundled Chromium next to the app binary — chromium/<platform>/... beside the executable, where the bundle step placed it (dist/<app>/chromium/... on Windows/Linux, dist/<app>.app/Contents/MacOS/chromium/... on macOS).
3. Bundled Chromium at the working directory — chromium/<platform>/... relative to the launch cwd.
4. Playwright's registry cache — the binary Playwright installed via deno run -A npm:playwright install chromium (development only; resolve() returns undefined, and the caller launches without an executablePath so Playwright uses its own cache).

import { chromium } from "@/core/facade.ts";
const exe = chromium.resolve(); // string | undefined

chromium.extensions() returns unpacked-extension folders shipped next to the binary (or under <cwd>/src/extensions in dev). Filter them with chromium.exists() before attaching.

Wiring it to the UI

Chromium run inside your backend controller, exposed as a binding:

// your controller: <module>.browser.visit
export const visit = async () => { /* chromium.resolve(), launch, navigate, close */ };
export const handlers = { visit };

// your UI component
const result = await bindings["<module>.browser.visit"]({ url, seconds, headless });

The registry convention is <module>.<controller>.<handler> — in-process, no HTTP/IPC; results come back as plain JSON (errors as { ok: false, error }, never as thrown exceptions).

Bundling Chromium & extensions

The bundle step can download Chromium into the bundle so the app carries a working browser. See Bundle and its flags.

Extensions are bundled only when Chromium is bundled (the default --chromium=auto). Every directory under src/extensions/ is treated as one unpacked extension and copied next to the binary — extensions/<name>/ on Windows/Linux, Contents/MacOS/extensions/<name>/ on macOS.

Attaching unpacked extensions

Each folder under src/extensions/ must be a real unpacked Chrome extension — a directory with a manifest.json at its root. A minimal one:

src/extensions/
└── my-extension/
    └── manifest.json      # name, permissions, content_scripts, background, etc.

To run Chromium with extensions attached:

• Playwright needs a persistent context (a temp profile) plus --load-extension launch args.
• Headless is forced off — the headless Chromium shell cannot load extensions.
• Everything else (navigate, wait, read title, close) works the same.

If you build that logic into your own binding, it will discover src/extensions/ automatically via chromium.extensions() — no hardcoding needed (see the chromium API page for the exact launch code).