Unknown warning in design mode

Question

When I launch my application in development mode, I get this warning message

GET "/assets/playerbg.png" will start for 127.0.0.1 on 2012-01-07 03:30:53 -0500

Service asset /playerbg.png - 304 Not changed (0ms)

[2012-01-07 03:30:53] WARN Failed to determine the length of the contents of the response body. Set the length of the content of the response or set Response # chunked = true

please, how can I refer to this post.

Answer 1

This is a problem with Webrick and ruby ​​1.9.3. Do not worry about anything.

If you use Thin , you will not see this warning.

Answer 2

I ran into the same problem. After adding the gem "webrick", "1.3.1" entry gem "webrick", "1.3.1" to my Gemfile for development mode, my problem is resolved.
You can turn to the same problem for additional help.