1 files changed, 3 insertions, 2 deletions
diff --git a/build.js b/build.js
index 4cb68f3..1a6f097 100644
--- a/build.js
+++ b/build.js
@@ -62,7 +62,7 @@ self.addEventListener('message', (e) => {
 // Activating keeps the previous build's cache beside the new one: a page
 // launched from the old shell (navigations to / are cache-first, below) keeps
 // running the old build until its next launch, and its lazily imported chunks
-// must still be found. Older caches go. Navigation preload starts a
+// must still be found. Older builds' caches go. Navigation preload starts a
 // navigation's network request while the worker itself is still starting.
 const META = 'coinos-sw-meta';
 self.addEventListener('activate', (e) => {
@@ -74,7 +74,8 @@ self.addEventListener('activate', (e) => {
     const keep = [CACHE, ...order.filter((k) => k !== CACHE)].slice(0, 2);
     await meta.put('cache-order', new Response(JSON.stringify(keep)));
     const keys = await caches.keys();
-    await Promise.all(keys.filter((k) => k !== META && !keep.includes(k)).map((k) => caches.delete(k)));
+    // only builds' caches: the thumbnail and call caches outlive a deploy
+    await Promise.all(keys.filter((k) => k.startsWith('cold-') && !keep.includes(k)).map((k) => caches.delete(k)));
     await self.clients.claim();
   })());
 });