Safari Intelligent Tracking Prevention: Third-Party Cookie Persistence Issues
0 reputation · 08 Sept 2021, 02:10 UTC
ITP and Storage Access API Behavior
The objective is to determine the precise persistence behavior of cookies within Safari's Intelligent Tracking Prevention (ITP) framework. ITP utilizes on-device machine learning to block trackers and caps first-party cookies set via JavaScript to a 7-day expiration for users who do not interact with the site. For third-party contexts, the Storage Access API is the documented mechanism for requesting cookie access, though this requires explicit user permission.
There is uncertainty regarding the consistency of these restrictions across different environments. Specifically, behavior may diverge between Safari on macOS and iOS due to system-level privacy constraints, and the efficacy of the 'Disable Intelligent Tracking Prevention' setting in the Develop menu for baseline testing is not fully defined.
Questions:
- Does the 7-day expiration cap for JavaScript-set cookies apply uniformly across Safari 17+ regardless of the interaction type?
- Does enabling 'Disable Intelligent Tracking Prevention' remove all ITP-related storage caps, or do system-level constraints persist?
- What specific user interaction triggers are required to reliably invoke the Storage Access API prompt within a third-party iframe?
