Option to enable mime header saving and displaying

Feature Proposal
1

An Option in the settings to enter a “Debug Mode” where mime headers are saved and displayed in message info.
This should be in all dc clients (desktop, android, iOS)

iOS has already implemented the flag in its settings, but there isn’t a way to access this information inside of the app, yet.

related:

2

closing stale issue.

ftr, we had smth like that in the past, but it is no longer needed for quite some time