iOS 15 now blocks email tracking in the Mail app. How to keep a healthy email list?

With iOS 15, Apple blocks the tracking of email opens in the Apple Mail app. MacOs and iPadOS coming (read more). That means we'll lose significant data at the open rate level.

The problem…

To keep our deliverability healthy, we don’t email people who didn’t open our emails in the last 365 days. That means a lot of people, who actually open our emails, will be excluded from our audiences, as Intercom will think they never opened an email.

What alternative ways do we have to keep our email list clean, without using this open email event?

Thanks!