For every new chat session (after each startup) Dino should warn once (or multiple times) with a red marker when a Message was received unencrypted.
I know that on the right side there is no encrypted symbol, but users might overlook this. Another idea is to add a red open lock to show that the messages are NOT encrypted. This is more obvious to me. And users dont get bothered too much.
Sample from pidgin:

Those types of warnings are extremely frustrating, but the red open lock seems like a good idea.
@d9h02f I agree. It would look like this, just with an open lock and no red timestamp.

Could someone explain what does this _read lock_ and _exclamation bubble_ mean (exclamation bubble was replaced with double checks (supposedly delivered))? Not sure why it is red. No body disabled encryption ..

It's definitely better to add a tooltip, I think. It's confusing.
In general, I think if there are any errors a normal human understandable message should always be shown. Not hidden behind a bubble.
Good cases are: Why was a message not delivered? Why was a message not send?
Those are "critical" issues. I think Dino does that already, however, it should mention always what happened. This enables more interaction and awareness with and to the user.
Since 853dfa2d6f0d1300b096f0c6a12ca179208f5287 unencrypted messages in encrypted conversations are highlightend with a red open lock.
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Could someone explain what does this _read lock_ and _exclamation bubble_ mean (exclamation bubble was replaced with double checks (supposedly delivered))? Not sure why it is red. No body disabled encryption ..
It's definitely better to add a tooltip, I think. It's confusing.