In D13119#370310, @kamil wrote:

Shouldn't we update all usages of isDesktopSafari that could be affected, e.g. in getCryptoKeyPersistentForm?

This is a very good question.
For keyserver based notifs it is not necessary to update getCryptoKeyPersistentForm since olm session encryption key is not persisted upon decryption. It is only persisted when session with keyserver is created and this requires opened app. Things are different for peer-to-peer notifications since notification can initiate encryption key generation and persistence since it can be session creation request.

I will continue investigation on Linear.