PostMessage bot missing icon and name

Question

Using my own bot, I can postMessage ( doc ) to the channel (with bot authenticator). However, the messages do not show my bot icon or name, just the bot is one by default:

When I change the theme, it works fine (i.e., the icon and name of my custom bot appear).

Is additional configuration required?

Answer 1

It seems like the parameter as_user=true needed. Doc is somewhat confusing in this regard:

 as_user Optional Pass true to post the message as the authed user, instead of as a bot 

The offline user in this case is the bot whose authentication token you used.