Letterboxing causes greyed out alert background to be mis-aligned
Steps to reproduce
- Visit
https://example.org. - Adjust window size to show Letterboxing padding.
- Open web console and trigger
alert("hello").
The greyed out background only covers the right and bottom padding.
This is caused by a combination of place-content: center on the .browserStack element and position: absolute on the .dialogStack element.
The grey background should probably cover the entire tab area. @donuts, can you confirm what area you want the grey background to cover?
/cc @ma1
