I am using WP 3.4.2 and Atahualpa 3.7.9.

I am looking for a plugin that makes my right sidebar (categories) collabsible. Anyone can help me with this one? http://bugholzmoebel.at

Thank you in advance!

Have you searched on wordpress.org?

Hi,

thank you, yes I have. I have chosen nice navigation which ads a little arrow and expands when select "list pages" in the widget. When selecting "list categories" I get dots instead and no expanding...

That's where testing several plugins comes in and/or contacting the plugin developer.