Hey bruno36,

It looks like you have at least one jquery conflict, this is most likely a plugin or even possibly the WP theme itself loading it’s own jquery library’s. Take a look at this page in the Codex.

To resolve this you could try disabling plugins one by one, and also try switching to one of the default WP themes to see if that resolves it.

I’m not sure if that’s responsible for the full width forum display or not, but it’s definitely a good place to start!

Also – what are your ‘theme display options’ in Forum > Integration > Page and Permalink?

Thank you ! the problem was well cause a plugin 

I do not regret my purchase! The customer service is wonderful and fast

Excellent! Glad you found the cause and happy to help.