Smal

frontend/src/i18n/locales/en.ts

@@ -917,7 +917,7 @@ const en = {
     body: 'Want to see property data around you? Use your location, or start the demo at Canary Wharf.',
     useLocation: 'Use my location',
     locating: 'Locating…',
-    useDefault: 'Show Canary Wharf',
+    useDefault: 'Show London',
   },
 
   // ── Mobile Drawer ──────────────────────────────────

frontend/src/lib/url-state.test.ts

@@ -196,6 +196,32 @@ describe('url-state', () => {
     expect(state.overlays).toEqual(new Set(['noise', 'crime-hotspots']));
   });
 
+  it('enables crime + trees overlays by default on a fresh visit', () => {
+    const state = parseUrlState();
+
+    expect(state.overlays).toEqual(new Set(['crime-hotspots', 'trees-outside-woodlands']));
+  });
+
+  it('round-trips an explicit "all overlays off" via the __none sentinel', () => {
+    const params = stateToParams(
+      null,
+      {},
+      [],
+      new Set(),
+      'area',
+      undefined,
+      undefined,
+      new Set()
+    );
+
+    expect(params.getAll('overlay')).toEqual(['__none']);
+
+    window.history.replaceState({}, '', `/?${params.toString()}`);
+    const state = parseUrlState();
+
+    expect(state.overlays).toEqual(new Set());
+  });
+
   it('round-trips satellite basemap selection', () => {
     const params = stateToParams(
       null,

frontend/src/lib/url-state.ts

@@ -48,7 +48,7 @@ import {
   type PoiFilterName,
 } from './poi-distance-filter';
 import { dedupeTravelTimeEntries } from './travel-params';
-import { isOverlayId, type OverlayId } from './overlays';
+import { isOverlayId, DEFAULT_OVERLAY_IDS, type OverlayId } from './overlays';
 import { CRIME_TYPES, isCrimeTypeValue } from './crime-types';
 import { isBasemapId, type BasemapId } from './basemaps';
 import {
@@ -59,6 +59,7 @@ import {
 
 const POI_NONE_PARAM = '__none';
 const CRIME_TYPES_NONE_PARAM = '__none';
+const OVERLAY_NONE_PARAM = '__none';
 const CRIME_OVERLAY_ID: OverlayId = 'crime-hotspots';
 
 export interface UrlState {
@@ -227,7 +228,7 @@ export function parseUrlState(): UrlState {
     hasExplicitView: false,
     filters: parseFilters(params),
     poiCategories: new Set(),
-    overlays: new Set(),
+    overlays: new Set(DEFAULT_OVERLAY_IDS),
     basemap: 'standard',
     colorOpacity: DEFAULT_COLOR_OPACITY,
     tab: 'area',
@@ -266,9 +267,14 @@ export function parseUrlState(): UrlState {
     }
   }
 
+  // Overlays default to DEFAULT_OVERLAY_IDS on a fresh visit; explicit `overlay`
+  // params override that, and the `__none` sentinel records "all off" so it
+  // survives a reload instead of silently restoring the defaults.
   const overlayParams = params.getAll('overlay');
   if (overlayParams.length > 0) {
-    result.overlays = new Set(overlayParams.filter(isOverlayId));
+    result.overlays = overlayParams.includes(OVERLAY_NONE_PARAM)
+      ? new Set()
+      : new Set(overlayParams.filter(isOverlayId));
   }
 
   // Crime-type filter: repeated `crimeType` params, or the `__none` sentinel.
@@ -451,8 +457,14 @@ export function stateToParams(
   }
 
   if (selectedOverlays) {
-    for (const overlay of selectedOverlays) {
-      params.append('overlay', overlay);
+    if (selectedOverlays.size === 0) {
+      // Distinguish a deliberate "all overlays off" from a fresh visit, which
+      // would otherwise re-apply the defaults on reload.
+      params.append('overlay', OVERLAY_NONE_PARAM);
+    } else {
+      for (const overlay of selectedOverlays) {
+        params.append('overlay', overlay);
+      }
     }
   }