Windows resizing after external monitor turns off in Full Screen

I use Parallels with an external monitor on my MBP. I run Parallels in full screen mode, in its own space.

When I'm idle and away from the machine, the screen saver turns on after a while (naturally), and then the monitor turns off after a while (naturally). However, when I come back, it's as if the monitor has trouble recognizing its mode or something. Parallels will load up in its own space in full screen, but all the individual windows that were open are now scrunched up into the upper left corner of the full screen window, and it almost looks like it thought it was running in 800x600 mode or maybe 1024x768 or something. I then have to go and move all those windows in Windows (ha) back and resize them.

This does not happen in coherence mode, and as far as I know, it doesn't happen if I just leave parallels running in a Mac window (i.e. not fullscreen mode). I like using Fullscreen mode in its own space, because it just allows all the "features" of Windows that I"m used to to be there.

 

Hi Joe Bennett. Please try this and let us know if it makes any difference: Take a snapshot, shut down Windows (as opposed to simply suspending it; see for details), open the virtual machine configuration window, navigate to Options -> Full Screen and select 'Keep Ratio' for 'Scale to fit screen:'. Close the window now and start Windows up.

 

I have confirmed that the same thing happens if it is running in a window. When it comes back from a suspended state where the display is off, the windows are in the top left corner and shrunk to fit a smaller display. The Parallels window itself will be the same size on my monitor, though.

 

Hemnath, this didn't do it. Same thing happened. Given that it happened in window-mode, too, something tells me that this is not just a Parallels thing - something is going on with communication between the monitor and the Mac during the screen coming up that the Mac things the resolution is "X" (much smaller), and this gets to Parallels, which dutifully tells the client OS the new resolution and it fixes the windows. Then, when it comes back a little later (maybe ms) with the right resolution, it's too late.

That's of course just a guess, and it is a problem given that this doesn't happen to any of my other native apps (i.e. Safari or Word or whatever running on the Mac don't experience this).

Note that this doesn't happen in coherence mode - only window and full-screen mode. I'm just not that big a fan (right now) of coherence mode)'

 

The monitor I have right now: A Samsung U28E590 4K display. It is connected to a 2017 15" MacBook Pro with 3.1 GHz i& and 16GB Ram. The monitor is connected via HDMI behind the Apple USB-C to Digital AV Multiport Adapter (gives you a USB-C, USB-A, and HDMI out).

This problem did not exist on the same monitor with my 2015 13" Macbook Pro that was connected via DisplayPort.

When I moved to this new Mac, I did it via porting my data from the other Mac (i.e. it wasn't a fresh install).

So, it could be some setting related to that, it could be some issue with the Multiport Adapter (maybe, for example, Parallels initially thinks it is connecting to the internal display?). Or it could be Parallels.

 

Sigh... well, it just happened in coherence mode now, too.

 

Can you please share a screenshot of this scenario?

 

I've tried. It now hasn't done it for two days. I can't explain it. What I can say is I've been paying a lot more attention, and I really do think it is related to the way the Mac laptop returns from screen-off, so maybe you can pass this onto the team. What I see sometimes on my native Mac windows is this: I will see the screen turn on, and come out of the screen saver. I will see the Mac windows positioned in the right place, with the correct WxH, but the content in side that window is not correct - it is scrunched into the upper left corner of that particular window. So, for example, I will see Safari come up, but let's say it is loaded on this page - only the upper left portion will be visible, and the rest will just be a grey box. After less than a second, the entire window will be displayed.

If I were to think of how to test this or see it, I would say log when you get geometry notifications from the OS, and see if you get multiple of them when coming back from a suspended screen, on a laptop, with the laptop lid closed, where the external display you are connected to is larger than the native display of the laptop.

If I happen to get this to happen, I *will* post the screen shot.

 

I had to shrink it to be able to upload it.
This is it happening when I was in "window" mode. So I've had it happen in "window" mode, "full screen" mode, *and* "coherence" mode.
I'm 99.99999% sure this is a bug/issue with the combination of MacOS, HDMI, my Samsung 4K monitor, the 2017 15" MBP, and the USB-C to HDMI dongle from Apple. The reason I say this is because the same VM was not having this issue on my 2015 13" MBP using mini-DP to this same monitor. And I've seen another app I use (Reeder) have a similar issue.

But I want to bring it to your attention to see if there is anything you can do like, if you see a geometry change, "wait" some number of milliseconds before accepting it, because you may very well get another one.