The Email Performance Dashboard excludes open events associated with the Mozilla/5.0 user agent to reduce inflated open rates caused by Apple Mail Privacy Protection (MPP).
Understand how MPP affects open tracking
MPP protects Apple Mail users by preloading email images, including the tracking pixel used to detect opens. This can create an open event even when the recipient hasn’t opened the email.
MPP-generated and genuine opens can look the same in the event data. Both can use the Mozilla/5.0 user agent, so the dashboard can’t reliably identify which opens represent real engagement.
See what the filter removes
The open rate formula excludes open events with the Mozilla/5.0 user agent. This means it removes:
- Automated opens generated by MPP
- Genuine opens from users whose Apple Mail activity uses the same user agent
As a result, the dashboard’s open rate may be lower than a calculation that includes every open event. The metric is designed to provide a more reliable view of measurable engagement rather than report all detected image loads.
Use clicks to measure engagement
MPP doesn’t affect click, delivery, or bounce metrics. Use click-through rate and other non-open metrics to evaluate genuine engagement from Apple Mail users.
Other bots and proxies, such as GoogleImageProxy or YahooProxy, can also generate open events. The dashboard doesn’t exclude these events because their effect on open rates isn’t large enough to require the same treatment.
For more information, see Apple Mail Privacy Protection.