Content.*/page.* context variables are not provided in dialog url

According to Confluence Cloud Developer page
https://developer.atlassian.com/cloud/confluence/context-parameters/

following context variables are supported: {context.id}, {space.id}

But following code in atlassian-connect.json
“url”: “/cpa-dialog?space={space.id}&pageId={content.id}&spaceKey={space.key}”

results in this url:
“cpa-dialog?space=&pageId=&spaceKey=&xdm_e=…”

As you can see, context parameters are blank for dialog.
Attaching atlassian-connect.json to reproduce the issues.

Is it somehow possible to determine id of the Confluence page that opened the dialog?

modules:{  
   webItems:[  
      {  
         location:"system.content.action/modify",
         weight:200,
         context:"product",
         target:{  
            type:"dialogmodule",
            options:{  
               key:"cpa-dialog"
            }
         },
         name:{  
            value:"==OPEN DIALOG=="
         },
         key:"cpa-menu-item",
         conditions:[  
            {  
               condition:"user_is_logged_in"
            }
         ]
      }
   ],
   dialogs:[  
      {  
         url:"/cpa-dialog?space={space.id}&pageId={content.id}&spaceKey={space.key}",
         options:{  
            chrome:false,
            width:"7680px",
            height:"4320px",
            header:{  
               value:"Confluence Dialog Title"
            },
            conditions:[  
               {  
                  condition:"user_is_logged_in"
               }
            ]
         },
         key:"cpa-dialog"
      }
   ]
}