2.2.1 Copied Panel is Blank

What 
 In certain circumstances, when you copy/paste a panel into another dashboard, you may find that the new panel is blank. 
 When/Why 
 This will happen most often if the dashboard that you copied from has variables defined that the panel relies upon.  For instance, if a panel relies on $host to be the address of your server, but the destination dashboard doesn't have that variable, then the panel will copy, but be blank. 
 How 
 Below you'll see the issue: 
 
 
 Fixing the issue requires replicating the variables in the destination dashboard.  (Unfortunately there is no method for copy/paste, so they must be regenerated.). In any dashboard, you can see the variables in Dashboard Settings → Variables: 
   then  
 Replicate the variables in your own dashboard: 
 
 And, once you save those new variables, you should find your copied panel now works: