Open Bug 1354102 Opened 7 years ago Updated 2 years ago

Dialogs are displayed at the wrong size when moved back and forth between screens with different dpi

Categories

(Core :: Widget: Win32, defect, P3)

Product:
Core
Component:
Widget: Win32
Platform:
x86
Windows
Type:
defect

Tracking

()

People

(Reporter: florian, Unassigned)

References

Details

(Whiteboard: tpi:+) 

I saw this on a Windows 10 laptop with an HiDPI internal screen and a lowdpi external screen, with Firefox windows on both screen.

When closing a window with multiple tabs on the external screen, I got a giant confirmation prompt. See http://i.imgur.com/vONKERX.png
Summary: Confirm prompts are displayed at the wrong size when shown on an external low dpi screen → Confirm prompts are displayed at the wrong size when shown on an external low dpi screen/monitor
Priority: -- → P3
Whiteboard: tpi:+
See Also: → 1428475
This one should be fixed by bug 1387340 which is on Nightly. Can you confirm?
Flags: needinfo?(florian)
This is mostly fixed; but the window sizes are not always quite correct.

My primary display is 2×. My external displays are 1×. In the past, things like the Confirm close dialog and the Help → About Nightly window have always been at 2× size, regardless of which screen they’ve been on.

I used continued to use these two test subjects: the “Confirm close” dialog, and the Help → About Nightly window (which is chrome://browser/content/aboutDialog.xul).

Screenshots: https://imgur.com/a/OuJK5

The incorrect window sizing occurs when the window is opened on the 1× display, or when it is opened on the 2× display, moved to the 1× display and then moved back to the 2× display (after which the window is stuck in the wrong size, not amplifying the error with each cycle through the different DPIs).

The window sizes are all a bit inconsistent. On the aboutDialog at 1×, the height difference is 19px and width difference 15px; on the confirm close dialog at 2×, it’s a height difference of 75dpx (37.5px) with no width difference.

My initial guess (based on a little DPI-awareness fiddling in Windows) is that calculations around the window chrome size (title bar and possibly edges) are being done incorrectly, but I’m not at all confident of that analysis given the apparent inconsistencies.
(In reply to Kartikaya Gupta (email:kats@mozilla.com) from comment #1)
> This one should be fixed by bug 1387340 which is on Nightly. Can you confirm?

Yes. I reproduced the bug again on a Nightly from 2018-01-08. After upgrading to the current Nightly (2018-01-16), I can't reproduce anymore. This matches the time frame when the fix in bug 1387340 landed.
Flags: needinfo?(florian)
Thanks. We're going to leave this bug open to continue tracking the issue in comment 2.
Summary: Confirm prompts are displayed at the wrong size when shown on an external low dpi screen/monitor → Confirm prompts are displayed at the wrong size when moved back and forth between screens with different dpi
Summary: Confirm prompts are displayed at the wrong size when moved back and forth between screens with different dpi → Dialogs are displayed at the wrong size when moved back and forth between screens with different dpi
Severity: normal → S3
You need to log in before you can comment on or make changes to this bug.