If you checked Source code, you then need to added the source code repository for your distro, or temporarily just change the main repo to source by clicking it and clicking edit then Type:Source, refresh and get the sources, then change it back. Or just copy the info from that repo and create a new one for the source only.
If you checked Source code, you then need to added the source code repository for your distro, or temporarily just change the main repo to source by clicking it and clicking edit then Type:Source, refresh and get the sources, then change it back. Or just copy the info from that repo and create a new one for the source only.