bug(browse): BROWSE_EXTENSIONS_DIR causes visible Chromium window on macOS

[yinanli1917-cloud]

Bug

PR #315 added Chrome extension support via BROWSE_EXTENSIONS_DIR. Two issues found:

1. Visible Chromium window on macOS. The --window-position=-9999,-9999 approach doesn't work — newPage() creates new windows that ignore startup position flags.

2. Extensions don't actually run. browser.newContext() creates an isolated context. Extensions only execute in the default browser context, so content scripts, service workers, and declarativeNetRequest rules were all silently inactive.

Root cause

• Playwright's chromium.launch() + browser.newContext() = isolated context = extensions invisible to pages
• --window-position only affects the initial browser window, not windows created by newPage() via CDP Target.createTarget

Fix

Submitted a follow-up PR with:

• launchPersistentContext() — extensions run in the default browser context
• --headless=new — no visible window (Chromium 112+ supports extensions in new headless mode)
• ignoreDefaultArgs to strip --disable-extensions and --enable-automation
• Cookie persistence across daemon restarts (~/.gstack/browse-cookies.json)

[time-attack]

@yinanli1917-cloud Chromium still opens a visible macOS window when BROWSE_EXTENSIONS_DIR is set, pending the selected implementation.

[yinanli1917-cloud]

I'm the one who originally filed this (#432, with a fix in #440). My earlier fix got overtaken by the v0.12 headed-mode work, so I closed it at the time. Coming back with fresh eyes:

Confirmed on macOS + Chromium 145 that --window-position=-9999,-9999 is ignored (the window lands on screen around 216,30) and the newContext() path leaves the extension inert. The fix is launchPersistentContext + Chrome's new headless mode (--headless=new): the extension's service worker loads with no visible window. Validated end to end with a real MV3 extension.

PR: #2281

[capy-ai]

BROWSE_EXTENSIONS_DIR now launches Chromium in new headless mode (--headless=new) with a persistent profile, so extensions run in pages and no window opens. Fixed in v1.91.19.0 (#3025).

We could only test this on Linux, not on macOS, so I'm leaving the issue open until you can confirm. Could you upgrade (run /gstack-upgrade in Claude Code, or on Codex and other env-var hosts cd <source from ./setup --status> && git pull && ./setup --host <host>) and let us know whether it works for you? If you still see this, please add ./setup --status output here.