Adds special logic to accommodate the ULS trigger being placed inside
modern Vector's sticky header, which has a fixed position and requires
the ULS menu to remain pinned to the page when scrolling.
Bug: T295391
Change-Id: Ic531dd2ae213f8221157386f79edb95bc61a8119
To avoid overlapping with the Vector sticky header, the z-index
should be lowered so that the sticky header is always
above it.
Bug: T295794
Change-Id: I9d3f45d56204bedc98d1994ed984b43f01c29fd5
Jan Drewniak