Apple implements 7-day cap on script-writable storage

In February 2019, Apple announced that "Intelligent Tracking Prevention" (ITP) would cap the expiry of client-side cookies to seven days.

As third-party scripts moved to other means of first-party storage such as LocalStorage, Apple decided to strengthen their policy to all script-writable storage. This change means that after seven days of Safari use without user interaction on a website, Apple will delete all script-writable storage, including first-party cookies and LocalStorage. Below are the script-writable storage forms affected (excluding some legacy website data types):

• Indexed DB

• LocalStorage

• Media keys

• SessionStorage

• Service Worker registrations and cache

Re-collect consent on websites

The new policy will impact websites utilizing the Didomi CMP on websites. Since February 2019, Didomi has used LocalStorage to avoid the consent re-collection for a website.Now that all script-writable storage is deleted, a website will be forced to re-collect end-user consent if seven days have lapsed since the end-user's last interaction with the website.