Window position offset by 8px after every 2nd restart
I use a 21:9 Monitor and for everyday use I have my window size set to te middle 2/3. When I restart Firefox the window shifts upwards by 8 pixel and after closing and restarting a second time the position is back to normal.
"screenY": switches between "0" and "-8" in xulstore.json
I wanted to add screenshots, but the image Upload is broken right now (Error 502 Bad Gateway)
I can repeat this indefinitely. Every 2n restarts the position is off and every 2n+1 it is correct.
I tried deleting xulstore.json but that didn't help. The screenshots where made with a new userprofile but that chaged nothing either.
All Replies (4)
I believe there is a default window border of 8px that is invisible, so when the window is in the upper left corner, it's actually at -8px on both axes.
But I don't know why the position measurement would ever change between sessions (except with the hidden privacy.resistFingerprinting setting enabled, which does various strange things).
How do you position the window in the middle 2/3 of the screen?
jscher2000 - Support Volunteer said
I believe there is a default window border of 8px that is invisible, so when the window is in the upper left corner, it's actually at -8px on both axes. But I don't know why the position measurement would ever change between sessions (except with the hidden privacy.resistFingerprinting setting enabled, which does various strange things). How do you position the window in the middle 2/3 of the screen?
Oh yeah I forgot to mention that resistFingerprinting is disabled.
I use an AutoHotKey script to set the window size. But even with the script not running it still happens.
I can even replicate it on another Laptop I recently set up with a fresh install of Windows10.
It only seems to happen, if the window is spanning from the top of the screen to the taskbar. If you manually drag the window size vertically Windows will "snap" the window to the screenheight.
If the window is even slightly smaller the 8px offset doesn't happen.
I generally used maximized windows, so can't speak from personal experience. I played with it a bit in a new profile and can't figure out exactly what Firefox is doing. (Composite screenshot sequence attached; Windows, snapped the window to the full height when I dragged the bottom edge down to the Taskbar, which may or may not be a factor.)
You can file a new bug, or search to see whether a bug has already been filed, over on https://bugzilla.mozilla.org/
