1) What client are you using?
2) What params are being logged for a create request?
3) What does the log show for a request sequence?
I have no experience with Carrierwave but are you sure that it's not
expecting a "remote_avatar_url" param by default, as Alexandre
suggested? That has nothing to do with whether you're using HTML
or not...
The code I posted was just to show you that Carrierwave requires that you add a suffix “remote_” and a prefix ‘_url’ to the parameter managed by carrierwave, in order for it to work with urls.
In your case the following code is not doing that, you are passing the the parameter ‘avatar’ without the sufix and the prefix.