Chrome Favicon D-Bus

Publish active Chrome tab metadata (title, URL, favicon) to D-Bus so Hyprland/Wayland/X11 tooling can consume it.

The extension sends JSON to a local HTTP endpoint, and a Rust daemon publishes enriched updates on D-Bus.

What this gives you

• Chrome extension emits active tab + Chrome window metadata.
• Rust daemon exposes updates over D-Bus signal: org.imalison.ChromeWindowInfo.Updated.
• Payload enrichment includes:
  • Hyprland active window and client list (hyprctl -j activewindow, hyprctl -j clients)
  • Hyprland IPC event state from .socket2.sock when available
  • Scored Hyprland candidate windows using focus, title, geometry, and cached continuity
  • X11 active window via xdotool when available
• Cached mapping from Chrome window_id -> Hyprland window address with confidence/source metadata.

Layout

• extension/manifest.json: Manifest V3 extension
• extension/background.js: Active-tab capture and localhost POST
• bridge-rs/Cargo.toml: Rust daemon crate
• bridge-rs/src/main.rs: HTTP -> D-Bus daemon
• systemd/chrome-favicon-dbus.service: Optional user service template

Extension transport

Extension posts to:

• http://127.0.0.1:38933/update

Chrome extension contexts can do outbound localhost fetch, but cannot host a local server or D-Bus service themselves.

Build and install daemon (Nix)

Build standard Linux package:

cd ~/Projects/chrome-favicon-dbus
nix build .#chrome-favicon-dbus

Run the built binary:

./result/bin/chrome-favicon-dbus --host 127.0.0.1 --port 38933 --path /update

Build static Linux package (musl):

cd ~/Projects/chrome-favicon-dbus
nix build .#chrome-favicon-dbus-static

Run without building explicitly:

cd ~/Projects/chrome-favicon-dbus
nix run .#chrome-favicon-dbus -- --host 127.0.0.1 --port 38933 --path /update

Install in profile:

cd ~/Projects/chrome-favicon-dbus
nix profile install .#chrome-favicon-dbus

Alternative non-Nix build

cd ~/Projects/chrome-favicon-dbus
cargo install --path bridge-rs --locked

Load extension

Chrome -> chrome://extensions -> Developer mode -> Load unpacked -> ~/Projects/chrome-favicon-dbus/extension

Note: Recent Google Chrome builds (including 145.x) reject command-line extension loading flags (--load-extension, --disable-extensions-except). Use chrome://extensions developer mode for unpacked installs.

Monitor D-Bus updates

gdbus monitor --session \
  --dest org.imalison.ChromeWindowInfo \
  --object-path /org/imalison/ChromeWindowInfo

Fallback if gdbus is unavailable:

dbus-monitor "type='signal',interface='org.imalison.ChromeWindowInfo',member='Updated'"

Each Updated signal carries one JSON string payload.

D-Bus contract

• Bus name: org.imalison.ChromeWindowInfo
• Object path: /org/imalison/ChromeWindowInfo
• Interface: org.imalison.ChromeWindowInfo
• Methods:
  • GetLastPayload() -> s
  • GetWindowPayloads() -> s (JSON object keyed by Hyprland window address)
  • GetSchema() -> s
• Signals:
  • Updated(s payload_json)
  • WindowUpdated(s window_id, s payload_json) (only for payloads with a Hyprland mapping)

Correlation hints for consumers

Useful fields from signal payload:

• chrome_window.id: Chrome internal window id
• chrome_window.left / top / width / height: Chrome window bounds used for Hyprland matching
• bridge.mapped_window.window_id: Best Hyprland address (when known)
• bridge.mapped_window.confidence: Score for the chosen mapping
• bridge.mapped_window.sources[]: Signals that contributed to the chosen mapping
• wm.hyprland_active.address: Current active Hyprland window address
• wm.hyprland_event_stream_connected: Whether the daemon is connected to Hyprland's event socket
• wm.hyprland_candidates[]: Top scored Hyprland windows considered for this Chrome update
• wm.hyprland_title_matches[]: Hyprland windows with similar Chrome tab titles
• wm.x11_active.id_decimal / wm.x11_active.id_hex: Active X11 window id

Optional: user systemd service

mkdir -p ~/.config/systemd/user
cp ~/Projects/chrome-favicon-dbus/systemd/chrome-favicon-dbus.service ~/.config/systemd/user/
systemctl --user daemon-reload
systemctl --user enable --now chrome-favicon-dbus.service

The provided unit uses %h/.nix-profile/bin/chrome-favicon-dbus. If you install with cargo install instead, update ExecStart accordingly.

Notes

• The daemon replies {"ok": true, "mapped": <bool>, "hyprland": <bool>} after the payload has been enriched and published. The extension only treats a snapshot as delivered when it was mapped (or no Hyprland backend exists), so unmapped windows are retried automatically.
• The extension re-pushes all windows every 30 seconds (chrome.alarms heartbeat) and retries failed sends with exponential backoff, so daemon restarts and dropped updates self-heal.
• Normal, popup, and app (PWA) windows are all published.
• If daemon is not running, extension retries with backoff and otherwise fails silently.
• Optional request auth is available with daemon --token <value> and extension support for X-Bridge-Token.