dsh-web-icon-indicator

LIMITATIONS

Known limitations

The favicon is a plain image, so browsers never run the SVG's own CSS/JS animation inside the tab UI — every frame is rendered here in JavaScript. How well a *changing* favicon is displayed differs by browser: | Browser | SVG favicon | Live per-state color/effect | Why | | --- | --- | --- | --- | | Chrome / Edge | ✅ | ✅ smooth | Re-reads `<link rel=icon>` live; `data:`-URI SVGs are fine. | | Firefox | ✅ | ✅ smooth | Renders SVG favicons well (and honors their `prefers-color-scheme`, unused here). | | Safari (macOS) | ✅ rendered static | ⚠️ best-effort | Ignores in-SVG CSS; aggressive icon caching. | | Safari (iOS) | ✅ rendered static | ⚠️ rarely | Unlikely to refresh without revisiting the tab. | Known limitations (current as of Safari 26.3): - **Favicons have their own cache.** Chrome keeps a favicon database, Firefox a `favicons.sqlite`, and **Safari a system-level icon cache** — none of which a normal *clear cache* touches, and WebKit even caches the "no icon" case. That is why a changed icon can linger for an existing tab. The plugin already mitigates this: it serves `base.svg` and the status endpoint with `Cache-Control: no-store`, bundles a freshness query (`?t=Date.now()`) on its fetches, and replaces the `<link rel=icon>` node on each state change. - **A theme-scoped favicon pair must be collapsed first (DSH ≥ 0.1.7).** The shell's `index.html` ships *two* `rel=icon` links — `favicon-dark.svg` for `prefers-color-scheme: dark` and `favicon.svg` for light — because up to `0.1.6-alpha.2` there was exactly one. A browser resolves the favicon to the **last connected link whose `media` matches**, so repainting only the first one left the tab showing the shell's icon no matter what the session did. The plugin now normalizes the set to a single always-matching link at startup (keeping the variant your scheme selects) before painting. If you are on a version before 0.5.2 and the tab icon simply never changes, this is why. - **Safari renders SVG favicons but ignores their internal CSS** — no `@media`, no `prefers-color-scheme`, no CSS animation. So all recoloring must be baked into each frame's markup (which the plugin does) rather than driven by CSS variables. - **`data:`-URI SVG favicons are unreliable in Safari** (WebKit bug 236616, still open; reproduced on Safari 17.6). The plugin currently builds each frame as a `data:image/svg+xml` URI, so on Safari the tab icon may not render at all — the biggest known gap. - **Dynamic JS updates in Safari are hit-or-miss;** they may require a reload, and Safari "locks onto" the first icon it sees. There is no guaranteed, spec-supported way to swap a favicon live in Safari today. - **Pinned-tab icon (`<link rel="mask-icon">`) uses its own cache**, separate from the regular favicon, and is a single-colour silhouette tinted by the `color` attribute — macOS + pinned-tab only, read at page load, not live. Full mechanics with sources (WebKit bugs, Stack Overflow, browser-engineering blogs) and a recommended path toward smoother Safari colour changes live in [`docs/safari-favicon-research.md`](./docs/safari-favicon-research.md).