open or use cache only if i'm offline

## **BEFORE YOU SUBMIT** please read the following:

* [. ] **I'm submitting a bug report**
* [ ] **I'm submitting a feature request**
* [ ] **I'm submitting a support request**

**webpack version:**
2.x

**sw-precache-webpack-plugin version**:
0.11.5

**Please tell us about your environment:**
Windows 10

**Browser:** [Chrome XX]

**Current behavior:**

**Expected/desired behavior:**

*If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem along with your:*

* **Webpack configuration:**

* **Generated service worker (not minified):**
hello i use laravel5.6 and Vuejs PWA, in my index page i have login form, if i'm authenticate i'm moving to dashboard page,
if i enter a true login and password, i have problem with axios 419 headers, because the page login is coming from service worker cache, so crdf token not generated again.
why when i press F5 the assets and pages come from service worker ?