Hi,
sorry for this, if it's just too obvious.
I've been trying to get the true colors to work with mosh, but somehow it always fails for me.
I use mosh 1.3.2 for both client and server. On macOS (10.13.1) I tried both the HomeBrew and compiled version. For the server I tried both macOS and Ubuntu 16.04 (with self-compiled mosh 1.3.2).
True Colors work flawlessly via SSH:

Using mosh 24bit colors are broken while 256 colors work:

I used this 24bit color test script.
I did read through #649 and #939.
Am I missing any additional configuration needed to make this work?
To sum up my environment:
xterm-256color settingTrue color support is not in 1.3.2, or any release, yet. You need to install Mosh from Git master, on both client and server. Fortunately this is really easy for both macOS and Ubuntu, use brew install --HEAD mosh and the Ubuntu PPAs.
@cgull Thanks for the help!
And sorry about the ticket, I thought 1.3.2 already included this feature.
Most helpful comment
True color support is not in 1.3.2, or any release, yet. You need to install Mosh from Git master, on both client and server. Fortunately this is really easy for both macOS and Ubuntu, use
brew install --HEAD moshand the Ubuntu PPAs.