diff --git a/CHANGELOG.md b/CHANGELOG.md
index f28dab6..1a6b3ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,12 @@
 The release notes on GitHub are taken from this file: the section whose
 heading is the version number.
 
+## 1.5.1
+
+- The web UI's scripts and styles are no longer kept by the browser across
+  an upgrade: after replacing the program, a normal reload shows the new
+  pages (before, an old app.js could stay in the browser's cache).
+
 ## 1.5.0
 
 Includes the changes listed under 1.2.3: the 1.2.3 release was built from
diff --git a/internal/api/server.go b/internal/api/server.go
index aed47f8..6a1d826 100644
--- a/internal/api/server.go
+++ b/internal/api/server.go
@@ -122,9 +122,10 @@ func (s *Server) Handler() http.Handler {
 	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set("X-Content-Type-Options", "nosniff")
 		w.Header().Set("Referrer-Policy", "no-referrer")
-		if r.URL.Path == "/" || r.URL.Path == "/index.html" {
-			w.Header().Set("Cache-Control", "no-cache")
-		}
+		// no-cache on every file: after an upgrade the browser must not keep
+		// the old app.js or app.css (the embedded files carry no date to
+		// revalidate against, so a cached copy could outlive the program)
+		w.Header().Set("Cache-Control", "no-cache")
 		static.ServeHTTP(w, r)
 	})
 	return mux