Unhappily using PRV in Multidock! [suddenly fixed?]

I've got the habit down now, but yet another pain...
 
It used to be so easy to simply dbl-click on a clip and the PRV opened fully zoomed to the location I clicked at...
 
Now I've gotta first do this to get the PRV open in the multidock, then shift-click to zoom it.... No shortcut around it... and if I change clips/tracks, I must repeat the entire process!
 
As I mentioned in an earlier thread about this, I think this time it's the fault of Microsoft and windows 8.1 which I'm unhappily trapped with due to hardware/software limitations... though I don't know if this would be a problem in win10 anyway....
 
I was working so well in win7 it's a shame I got pushed into this! <sigh>
 
OK... This is nuts...
 
After many days and hours of trying... Right after I posted this, I tried yet again... First opening the PRV in the multidock, issuing the zoom/max command, then dragging it out of the multidock and positioning it somewhere close to where I was previously used to. I was going to simply get used to it not being quite full-fit as that is what I was continually getting when I dragged it out of the multidock...
 
But this time, it seems to have snapped into the correct position fully filling the area???
 
I'm stumped.... What did I do differently this time?
 
Here's hoping it stays "fixed" ;-)
 
Sorry for yet another knowledgeable "fix"!