Document the patch calling convention once in lib/default.nix; patch
headers say what, target, hook, state and contracts. Comments only, no
code changes.
With maxRows capping the scroller, the inner grid panel scrolls (as in
Steam's own design, where the outer element holds the fixed edge shadows).
The fade/shadow state is now read from whichever of the two overflows and
updated on the panel's scroll events too, so the shadows show only where
more content is.
Besides the ScrollFade mask, the scroll region has ::before/::after shadows
toggled by stale can-scroll classes; with everything visible the bottom
shadow still covered the last row. Checker covers the shadow CSS.
launcherMenu.grid = { enable; columns; maxRows; } restyles the "+" menu's
programs section as a grid of tiles (icon, name below): Steam's own items
stay in place, maxRows limits the visible rows, and Steam's scroll fade is
recomputed so it only shows where there is more to scroll. The pinned
Desktop row is slim and centred in tile mode.
launcherMenu.iconFallbacks (default utilities-terminal, preferences-system)
installs hicolor copies of Breeze app icons, since Steam resolves program
icons only in hicolor; Konsole and KDE System Settings had none.
The checker gains checkOnly "stylesheet" signatures (matched against the
bundle's CSS files) to cover the scroll fade's gradient; launcher-menu-grid
signatures cover the section keys and the ScrollFade classes.
Pierre Kisters