M3's colour list for a standard toolbar ends "Standard button
(Primary)" and the vibrant list ends "Standard button (On primary
container)" (N-13) — both name the *standard* button. The two rules
painted every icon button in the toolbar instead, so a button that
brings its own container got a primary label on a primary fill and its
icon disappeared: SealShare's floating navigation marks the current page
with a filled button, and that button came out a blank circle.
A button that fills its own container is now left alone — filled, tonal,
or either of them selected — and keeps the label colour that goes with
the fill. A disabled button still falls back to button.css's disabled
ink in a toolbar of either colour, as before. AppBarTest pins the
exclusion on both rules.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
