We've face same issue. Starting from iOS 14 - there are some occurrences of UNNotificationContentExtension not being called at all. Judging from logs - UNNotificationServiceExtension works fine and stores image as an attachment, but UNNotificationContentExtension isn't triggered when user performs force touch on PN.
Only blank UI is seen with extension actions on the bottom (that were configured from the main app).
This doesn't happen 10/10 which makes it much harder to reproduce, but still it's a huge pain for users that rely on Rich Notifications.
m0rf
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