After an upgrade to Bamboo 5.6, when selecting a project from the dashboard multiple "Configure" buttons show up on the page:

Cause

This problem is caused by Utility Belt Bamboo plugin even though it's listed as compatible with Bamboo 5.6.

Workaround

Navigate to Bamboo Administration - > Plugins - > Manage Add-ons, disable "Utility Belt" Bamboo add-on and restart Bamboo. 

Check for any third party plugins  that are enabled and were compatible with the previous version of Bamboo installed on the server, but are not compatible with Bamboo 5.6 yet and disable them to avoid similar issues.