If you use Firefox on a large external screen and then disconnect and use it on a laptop, when you start Firefox, it appears partially offscreen.
If you immediately close it and open it again, it still appears offscreen, but in a different way.
Sometimes its the top, sometime it's the left, sometimes it's the right.
To recreate, place a xulstore.json in your profile that looks like this and then start Firefox.
{"chrome://browser/content/browser.xhtml":{"main-window":{"screenX":"0","screenY":"-342","width":"2463","height":"1204","sizemode":"normal"},"sidebar-box":{"sidebarcommand":"","style":""},"sidebar-title":{"value":""}}}
We appear to have fixed bugs like this in the past, but it comes back for some reason.
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If you use Firefox on a large external screen and then disconnect and use it on a laptop, when you start Firefox, it appears partially offscreen.
If you immediately close it and open it again, it still appears offscreen, but in a different way.
Sometimes its the top, sometime it's the left, sometimes it's the right.
To recreate, place a xulstore.json in your profile that looks like this and then start Firefox.
{"chrome://browser/content/browser.xhtml":{"main-window":{"screenX":"0","screenY":"-342","width":"2463","height":"1204","sizemode":"normal"},"sidebar-box":{"sidebarcommand":"","style":""},"sidebar-title":{"value":""}}}
We appear to have fixed bugs like this in the past, but it comes back for some reason.
Other apps reposition and size themselves to fit on screen when they are off screen or too large for the screen