Well the first side effect is related to the second one.
QML gets into a loop when the height changes. According to StackOverflow, a Connections QML object should do the trick:
https://stackoverflow.com/questions/31670920/qt-quick-5-5-how-to-omit-binding-loop-detected-for-property-warning-qml

@daneos What do you think?

Nevertheless, great job!

I don't know what I'm doing wrong, but if I do anything other than setting the height directly, the messages still end up clipped (but the code setting the height is run, for sure, I have a debug message there).
What I tried:

• onContentHeightChanged
• onContentSizeChanged
• onTextChanged
• onHeightChanged
• onPaintedHeightChanged
• Connections object, which gives me just QML Connections: Cannot assign to non-existent property "..." for all of the above
• Component.onCompleted
• and a few other signals, that unfortunately aren't emitted in this case

I posted a question on StackOverflow, so maybe someone will know how to do that properly.

I noticed another problem with messages height, I recently received a really long message, and it seems there is some limit (may be related to screen height, I think). What's also interesting, I can't enter this conversation again, as the application just dies after loading messages. I was not able to reproduce it on the emulator, so I will try to debug this on the device, when I learn how to do it :)

Hmmm the same fix is applied in #210 closing this one...