tabstrip

A browser tab strip for waybar, fed by tabctl. It shows the tabs of every browser window on the current workspace as clickable chips. Each chip carries the site favicon. Click a chip to activate the tab. Scroll to cycle.

The strip is scoped to the workspace, not to the focused window. Every chip is therefore a tab you can currently see, and the strip stays populated while a terminal or an editor has focus. Windows are ordered by screen position. Tabs are ordered by tab-bar position.

Built for Hyprland. One Go binary, plus resvg for SVG favicons.

How it works

browser extension → tabctl-mediator → D-Bus → tabstrip daemon → snapshot JSON → waybar

The daemon listens for tabctl's TabsUpdated D-Bus signal and for Hyprland window events. It then rewrites the snapshot file and signals waybar with SIGRTMIN+8. If the D-Bus signal is unavailable, the daemon polls every 1.5s.

Tab changes reach the bar in about half a second. Most of that is deliberate debounce.

Requirements

• tabctl 2.2.0 or newer, with its browser extension installed. Run tabctl list to confirm it works. Both halves must be 2.2.0: the strip reads favicons through ListTabsWithIcons, and the extension supplies favIconUrl. Run tabctl status to see both versions.
• waybar
• Hyprland. Workspace and window queries use its IPC sockets.
• resvg, to rasterise SVG favicons. Optional: without it SVG icons fall back to the browser chip and everything else still works. Go's image decoders cover the raster formats in-process. On Arch, pacman -S resvg.

Install

go install github.com/slastra/tabstrip@latest

Or clone the repository and run go build.

Usage

tabstrip daemon    run persistently, spawned by a hidden waybar module
tabstrip snapshot  one-shot refresh (debugging; default)
tabstrip goto N       activate the Nth displayed tab
tabstrip next         cycle to the next tab
tabstrip prev         cycle to the previous tab
tabstrip list         all tabs across every browser window, as JSON —
                      id, title, chip path, windowId, active, browser.
                      Unlike the daemon's snapshot (deliberately filtered
                      to the focused workspace), this is the global view,
                      for building a tab switcher.
tabstrip activate ID  activate a tab anywhere by its "<browser>.<win>.<tab>"
                      id, routed to the mediator that owns it

Waybar wiring

A hidden driver module runs the daemon. An image module renders the chips.

"custom/fftabsdrv": {
    "exec": "tabstrip daemon",
    "return-type": "json",
    "format": "{}",
    "tooltip": false
},
"image#fftabs": {
    "exec": "jq -c '[.tabs | to_entries[] | {path: .value.icon, marker: (if .value.active then \"active\" else \"inactive\" end), tooltip: .value.label, \"on-click\": (\"tabstrip goto \" + ((.key+1)|tostring))}]' $XDG_RUNTIME_DIR/waybar-fftabs.json",
    "signal": 8,
    "on-scroll-up": "tabstrip next",
    "on-scroll-down": "tabstrip prev"
}

The image module takes the chip count from the array, so per-tab slot modules are not needed. Waybar's image module has no CSS class states. The daemon therefore writes a dimmed copy beside each chip and selects between them.

Brightness marks the window you are in. Every tab of the focused browser window is bright and every other window on the workspace is dimmed, so the strip shows at a glance which chips belong to the window in front of you. When focus is on something that is not a browser, the daemon falls back to marking each window's active tab.

A text-only strip is still possible with custom/ slot modules. Read .tabs[N].label in each module and set a class from .tabs[N].active. Those modules cannot show favicons.

Favicons

Chips use the favicon the browser already resolved. tabstrip does not guess one from the domain and does not call a third-party icon service. Most favicons arrive as inline data: URIs, so the common case makes no network request.

Decoding runs in-process. PNG, JPEG and GIF use the standard library. SVG is rasterised at 256px and downsampled. ICO is parsed directly, because ICO directory headers often disagree with their payloads. One favicon declared 256x256 entries that held 16x16 PNGs. tabstrip therefore ignores the declared sizes, decodes every entry, and keeps the largest real one.

A tab with no usable favicon falls back to its browser icon, so rows stay aligned. tabstrip records a failure for six hours instead of retrying it on every tab event.

The daemon owns the cache and writes chips as tabs appear. Other tools can read the same files. Each chip is named <sha256(favIconUrl)[:16]>-processed.png and is 64x64 with rounded corners.

Configuration

There is no config file. The two values worth changing are environment variables, set on the waybar exec line that already starts the daemon.

Variable	Default	Purpose
TABSTRIP_MAX_TABS	16	chips to render before truncating
TABSTRIP_ICON_DIR	$XDG_CACHE_HOME/tabctl/favicons	favicon cache location

"custom/fftabsdrv": { "exec": "TABSTRIP_MAX_TABS=24 tabstrip daemon", ... }

How many chips fit depends on your screen width, so raise the cap if the strip stops short of the tabs you have open. Tabs past the cap are dropped silently.

Files

Path	Purpose
$XDG_RUNTIME_DIR/waybar-fftabs.json	snapshot the chips render from
$XDG_RUNTIME_DIR/waybar-fftabs.pid	daemon pidfile, newer instances replace older ones
$XDG_CACHE_HOME/tabctl/favicons/	favicon chips, written by the daemon, readable by other tools

License

MIT