caddyplug reports plugins installed, but caddy does not

[DarrienG]

Info:

(with go111module=on)

yak@ubuntu-yak:~$ go version
go version go1.12.7 linux/amd64

yak@ubuntu-yak:~$ caddyplug list
fetching missing dependencies: caddy, dnsproviders, hook.pluginloader
go: finding github.com/abiosoft/caddyplug latest
done fetching depedencies.

http:
 ✓ grpc
...

yak@ubuntu-yak:~$ caddyplug install-caddy
fetching missing dependencies: caddy, dnsproviders, hook.pluginloader
go: finding github.com/abiosoft/caddyplug latest
done fetching depedencies.

installing Caddy...
go: finding github.com/caddyserver/caddy/caddy latest
  ✓ installed Caddy in /home/yak/go/bin/caddy
yak@ubuntu-yak:~$ /home/yak/go/bin/caddy -plugins                                              
Server types:                          
  http                                 
                                                                                                                       
Caddyfile loaders:                                                                             
  short                                                                                        
  flag                                                                                         
  default                                                                                                              
                                                                                                                                                                                                                                               
Other plugins:                         
  http.basicauth                                                                                                       
  http.bind                                                                                                            
  http.browse                                                                                                          
  http.errors                                                                                                          
  http.expvar                          
  http.ext                             
  http.fastcgi     
  http.gzip                                                                                                            
  http.header                                                                                                          
  http.index                                                                                                           
  http.internal   
  http.limits                                  
  http.log                                     
  http.markdown                                
  http.mime                                    
  http.pprof                                   
  http.proxy                                   
  http.push                                    
  http.redir                                               
  http.request_id                                          
  http.rewrite                                             
  http.root                                                
  http.status                                              
  http.templates                                           
  http.timeouts                                            
  http.websocket                                           
  on                                                       
  tls                                                      
  tls.cluster.file