The Quick Settings pane is now too big for the screen. It goes past the right edge of he display, with no horizontal scroll bar to let me see the missing part. I use Firefox 63.0.1 (64-bit) on a desktop, with Windows 10 & a 1920x1080 screen.
Thank you for reporting this issue! I wanted to follow-up and let you know that we did indeed have a bug with some resolutions. The fix has been coded up and we are testing it. I would imagine in the next week or so this should be fully fixed for all accounts.
Thanks for bringing it up to us! Please keep the feedback coming!