When the Streams Studio IDE starts, if there are Application Set projects existing in the workspace, there are problem markers indicating that some or all of the build configurations cannot be found even though the build configurations exist.
Unexpected error markers on Application Set Projects when Streams Studio is restarted.
Example: The AppSetSchemaSharing project shows error markers in the Application Set Project, and 'Build configuration cannot be found' error messages in the Problems view.
Streams Studio 18.104.22.168
Resolving the problem
To remove the errant problem markers, close and then re-open one of the application set projects in the workspace. This will remove all errant "build configuration cannot be found" problem markers for all application set projects in the workspace.