Move to all PNGs in webmanifest.

app/frontend_static.py

@@ -135,7 +135,34 @@ def register_frontend_static_routes(app: FastAPI, frontend_dir: Path) -> bool:
             "display_override": ["window-controls-overlay", "standalone", "fullscreen"],
             "theme_color": "#111419",
             "background_color": "#111419",
+            # Icons are PNG-only on purpose. iOS Safari's manifest parser has
+            # historically been unreliable with SVG icons, and Android/Chrome
+            # PWA install flows prefer PNG for the install prompt.
+            #
+            # The "any" purpose entries are what iOS and desktop Chrome use
+            # for the home-screen / install icon. "maskable" entries are
+            # Android-only (adaptive icon with safe-zone crop); iOS does not
+            # apply the safe-zone mask, so a maskable-only icon set would
+            # render with excessive padding.
             "icons": [
+                {
+                    "src": f"{base}favicon-96x96.png",
+                    "sizes": "96x96",
+                    "type": "image/png",
+                    "purpose": "any",
+                },
+                {
+                    "src": f"{base}apple-touch-icon.png",
+                    "sizes": "180x180",
+                    "type": "image/png",
+                    "purpose": "any",
+                },
+                {
+                    "src": f"{base}favicon-256x256.png",
+                    "sizes": "256x256",
+                    "type": "image/png",
+                    "purpose": "any",
+                },
                 {
                     "src": f"{base}web-app-manifest-192x192.png",
                     "sizes": "192x192",
@@ -148,18 +175,6 @@ def register_frontend_static_routes(app: FastAPI, frontend_dir: Path) -> bool:
                     "type": "image/png",
                     "purpose": "maskable",
                 },
-                {
-                    "src": f"{base}favicon.svg",
-                    "sizes": "any",
-                    "type": "image/svg+xml",
-                    "purpose": "any",
-                },
-                {
-                    "src": f"{base}favicon-256x256.png",
-                    "sizes": "256x256",
-                    "type": "image/png",
-                    "purpose": "any",
-                },
             ],
             "screenshots": [
                 {

tests/test_frontend_static.py

@@ -69,7 +69,12 @@ def test_valid_dist_serves_static_and_spa_fallback(tmp_path):
         assert manifest["scope"] == "http://testserver/"
         assert manifest["id"] == "http://testserver/"
         assert manifest["display"] == "standalone"
-        assert manifest["icons"][0]["src"] == "http://testserver/web-app-manifest-192x192.png"
+        icon_srcs = {icon["src"] for icon in manifest["icons"]}
+        assert "http://testserver/web-app-manifest-192x192.png" in icon_srcs
+        assert "http://testserver/web-app-manifest-512x512.png" in icon_srcs
+        # SVG icons cause inconsistent PWA icon rendering on iOS; the manifest
+        # must be PNG-only.
+        assert all(icon["type"] == "image/png" for icon in manifest["icons"])
 
         file_response = client.get("/robots.txt")
         assert file_response.status_code == 200
@@ -152,7 +157,9 @@ def test_webmanifest_includes_forwarded_prefix(tmp_path):
         assert data["start_url"] == expected_base
         assert data["scope"] == expected_base
         assert data["id"] == expected_base
-        assert data["icons"][0]["src"] == f"{expected_base}web-app-manifest-192x192.png"
+        icon_srcs = {icon["src"] for icon in data["icons"]}
+        assert f"{expected_base}web-app-manifest-192x192.png" in icon_srcs
+        assert f"{expected_base}web-app-manifest-512x512.png" in icon_srcs
 
 
 def test_first_available_prefers_dist_over_prebuilt(tmp_path):