1266377 - Trouble re-scaling content at some stages while transition from hidpi to lowdpi monitor

Status: NEW

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

Description

[Bogdan Maris [:bogdan_maris], Release Desktop QA]

[Note]:
- This has been logged as a followup of bug 1265977 comment 1 and comment 4

[Affected versions]:
- latest Nightly 48.0a1

[Affected platforms]:
- Windows 10 64-bit

[Steps to reproduce]:
1. Open Firefox
2. Drag Firefox on lowdpi monitor
3. Move Firefox to hidpi monitor just a little (Just before it resizes on hidpi).
4. Move cursor to hidpi and from there 'slowly' complete the action of moving Firefox to hidpi. (Grab Firefox from an area near close, maximize, minimize buttons)

[Expected result]:
- Firefox re-scales nicely during transition of Firefox window from one screen to another.

[Actual result]:
- At some stages Firefox forgets re-scaling it's content.

[Regression range]:
- This is not a regression range it appeared after fixing bug 1264193. On older builds, Firefox would have broken layout and this cosmetic issue could not be seen.

[Additional notes]:
- I left Aurora 47 as unaffected because of bug 1265977 not being fixed in 47 yet. After the fix from bug 1265977 will arrive in 47 as well, it will be affected as well most likely.

Comment 1

[Laura Verdoes]

Moving Firefox between displays with different DPI settings by dragging with the mouse seems to be working fine for me. 

However if I move Firefox (while it is maximized) using the key combination Windows+Shift+Left/Right arrow key, content does not re-scale correctly. The page is not scaled at all, and UI text is also not re-scaled.

Comment 2

[Jonathan Kew (:jfkthame)]

(In reply to Ruben Verdoes from comment #1)
> However if I move Firefox (while it is maximized) using the key combination
> Windows+Shift+Left/Right arrow key, content does not re-scale correctly. The
> page is not scaled at all, and UI text is also not re-scaled.

This sounds like a distinct issue, not the same as the problem described here. However, I can't seem to reproduce it at the moment in my testing.

Please file a new bug report, and give details of the exact system and Firefox versions where you're seeing this problem. Thanks!

Comment 3

[Sylvestre Ledru [:Sylvestre]]

Moving to p3 because no activity for at least 1 year(s).
See https://github.com/mozilla/bug-handling/blob/master/policy/triage-bugzilla.md#how-do-you-triage for more information

Comment 4

[Sylvestre Ledru [:Sylvestre]]

Moving to p3 because no activity for at least 1 year(s).
See https://github.com/mozilla/bug-handling/blob/master/policy/triage-bugzilla.md#how-do-you-triage for more information