Canonical: https://rom-weaver.com/docs/webapp-status

# Webapp masthead metadata

The webapp masthead shows build identity, the configured thread count, and two independent runtime facts in one text row.

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## Table of contents

- [Build and thread values](<#build-and-thread-values>)
- [Runtime values](<#runtime-values>)
- [Theme](<#theme>)

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## Build and thread values

| Value | Meaning |
| --- | --- |
| `vX.Y.Z` | The application version. |
| `vX.Y.Z+N` | A build made `N` commits after that version. The `+N` is omitted on the version commit. |
| `abcdef0` (`sha`) | The seven-character commit identifier for a clean build. |
| `abcdef0*` (`sha*`) | The source commit with `*` appended; `*` means uncommitted changes were present when the build was made. |
| `10 threads` | The full thread-count label shown on desktop. |
| `10T` | The compact mobile thread-count label; `T` means threads. |

The version text normally looks like `vX.Y.Z · abcdef0`. The full build identifier, including a branch or dirty-build suffix when applicable, is available from the version tooltip.

## Runtime values

| Value | Meaning |
| --- | --- |
| `web` | The page is running in a normal browser tab or window. |
| `pwa` | The page was launched as an installed/standalone PWA. A PWA can also use a service worker. |
| `sw` | A service worker controls the page or is installed and ready to take control. Its tooltip distinguishes those states. |
| `sw off` | Service-worker offline support is disabled, unavailable, or registration failed. |

The first value describes how the page was launched; the second describes service-worker state. The combinations are therefore independent, such as `web · sw`, `pwa · sw`, or `pwa · sw off`. The prerendered shell resolves known runtime state before first paint, then React hydrates that shell in place instead of replacing the masthead nodes. While service-worker state is still unknown, the shell preserves the `sw` placeholder and adds a tooltip after the state resolves.

The thread count is shown as `· 10 threads` on desktop and `· 10T` on mobile to preserve masthead space. The full wording remains available to assistive technology and in the tooltip.

## Theme

The theme control offers light, dark, and system appearance. System appearance follows the device preference. Documentation screenshots use the active theme.

Procedure: [Change browser preferences](<https://rom-weaver.com/docs/browser-settings.md#change-preferences>).