From 089fcf94f8969b432ba113b18a924cd85836ab05 Mon Sep 17 00:00:00 2001
From: Rosa Gutierrez <rosa@37signals.com>
Date: Fri, 6 Feb 2026 12:37:39 +0100
Subject: [PATCH] Preload resources after service worker installation

When the service worker is registered for the first time, resources loaded
before it becomes active won't go through the service worker. These resources
may be served from the browser's HTTP cache on subsequent requests, bypassing
the service worker cache entirely.

The new `preload` option accepts a regex pattern. On first visit (when no
controller exists), it waits for the service worker to take control, then
sends a message with URLs from `performance.getEntriesByType("resource")`
that match the pattern. The service worker fetches and caches these resources.
---
 Gemfile.lock                           | 2 +-
 Gemfile.saas.lock                      | 2 +-
 app/javascript/initializers/offline.js | 7 ++++---
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/Gemfile.lock b/Gemfile.lock
index 9dd682dce..758936188 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -13,7 +13,7 @@ GIT
 
 GIT
   remote: https://github.com/hotwired/turbo-rails.git
-  revision: 0becdbbcdbf607eab6632463bc63f94d64249b7b
+  revision: ca62e8bdad88d01914d512ad24424e0670f239c9
   branch: offline-cache
   specs:
     turbo-rails (2.0.23)
diff --git a/Gemfile.saas.lock b/Gemfile.saas.lock
index 8f5c9dd95..a3552dacd 100644
--- a/Gemfile.saas.lock
+++ b/Gemfile.saas.lock
@@ -62,7 +62,7 @@ GIT
 
 GIT
   remote: https://github.com/hotwired/turbo-rails.git
-  revision: 0becdbbcdbf607eab6632463bc63f94d64249b7b
+  revision: ca62e8bdad88d01914d512ad24424e0670f239c9
   branch: offline-cache
   specs:
     turbo-rails (2.0.23)
diff --git a/app/javascript/initializers/offline.js b/app/javascript/initializers/offline.js
index c5eff824e..446a9671e 100644
--- a/app/javascript/initializers/offline.js
+++ b/app/javascript/initializers/offline.js
@@ -1,6 +1,7 @@
 import { Turbo } from "@hotwired/turbo-rails"
 
-Turbo.offline.start("/service-worker.js", { 
-  scope: "/", 
-  native: true 
+Turbo.offline.start("/service-worker.js", {
+  scope: "/",
+  native: true,
+  preload: /\/assets\//
 })