1489439 - window gaps(left/right edge) when restoring previous sessions

Status: NEW

(Firefox :: Session Restore, defect, P3)

Description

[Alice0775 White]

Build ID 	20180906100252
User Agent 	Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:64.0) Gecko/20100101 Firefox/64.0

Reproducible: always

Steps To Reproduce:
1. Open browser and change sizemode to normal
2. Adjust browser position so that left edge of browser will touch screen left edge.
   OR
   Adjust browser position so that right edge of browser will touch screen right edge.
3. Open some web page
   --- please remember the position of browser
4. Quit browser(Alt > File > Exit)

5. Start browser again
   --- The browser is opened correctly at the previous position

6. Do "Restore Previous Session" (Alt > History> Restore Previous Session)
   --- Bug appears

Actual Results:
Even though the current position is the same as the previous position, "Restore Previous Session" moves the browser window to something wrong position.


Expected Results: 
"Restore Previous Session" should not change the position of browser if current position is same as the previous position.

Comment 1

[Alice0775 White]

It needs disable Snap Assist in Windows 10.
System Settings >  Multitasking> “Snap” category on the right > Turn off all.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

The bug has a release status flag that shows some version of Firefox is affected, thus it will be considered confirmed.