Originally Posted by raymor

To confirm what Why said, yes. Any and plugins work fine with Strongbox. Wordpress tells the plugin what the username is. The plugins don't know or care that earlier Strongbox told Wordpress what the user name is.

The only exception would be certain plugins which themselves do authentication (log in). If the plugin logs people in based on, say, a VBulletin database, it would be expecting to handle log in and if improperly coded might not respect the fact that they have already logged in via Strongbox. Even in those cases, there are two simple solutions. Either a) simply set Strongbox to authenticate against vbulletin database, making the other plugin unnecessary, or b) fix the other plugin to check to see if they are already logged in.