On a phone the feed list is a drawer slid off the screen to the left, and it kept its shadow
there, which fell back across the page: the left 30px or so of the top bar and everything under
it were darker, in every theme (Glass light 231,233,243 at the edge against 246,247,255). Beside
the flat strip iOS paints above the page it made a seam at the top-left corner (#147).
Hiding the closed drawer instead (visibility) would also have done it, but every phone test
starts by waiting for the feed list to be visible, which off the screen it still counts as.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>